/*!
 * Less - Leaner CSS v3.9.0
 * http://lesscss.org
 *
 * Copyright (c) 2009-2018, Alexis Sellier <self@cloudhead.net>
 * Licensed under the Apache-2.0 License.
 *
 */

/** * @license Apache-2.0
 */

(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.less = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
        var addDataAttr = require('./utils').addDataAttr,
            browser = require('./browser');

        module.exports = function(window, options) {

            // use options from the current script tag data attribues
            addDataAttr(options, browser.currentScript(window));

            if (options.isFileProtocol === undefined) {
                options.isFileProtocol = /^(file|(chrome|safari)(-extension)?|resource|qrc|app):/.test(window.location.protocol);
            }

            // Load styles asynchronously (default: false)
            //
            // This is set to `false` by default, so that the body
            // doesn't start loading before the stylesheets are parsed.
            // Setting this to `true` can result in flickering.
            //
            options.async = options.async || false;
            options.fileAsync = options.fileAsync || false;

            // Interval between watch polls
            options.poll = options.poll || (options.isFileProtocol ? 1000 : 1500);

            options.env = options.env || (window.location.hostname == '127.0.0.1' ||
            window.location.hostname == '0.0.0.0'   ||
            window.location.hostname == 'localhost' ||
            (window.location.port &&
                window.location.port.length > 0)      ||
            options.isFileProtocol                   ? 'development'
                : 'production');

            var dumpLineNumbers = /!dumpLineNumbers:(comments|mediaquery|all)/.exec(window.location.hash);
            if (dumpLineNumbers) {
                options.dumpLineNumbers = dumpLineNumbers[1];
            }

            if (options.useFileCache === undefined) {
                options.useFileCache = true;
            }

            if (options.onReady === undefined) {
                options.onReady = true;
            }

            if (options.relativeUrls) {
                options.rewriteUrls = 'all';
            }
        };

    },{"./browser":3,"./utils":11}],2:[function(require,module,exports){
        /**
         * Kicks off less and compiles any stylesheets
         * used in the browser distributed version of less
         * to kick-start less using the browser api
         */
        /* global window, document */

// TODO - consider switching this out for a recommendation for this polyfill?
// <script src="https://cdn.polyfill.io/v2/polyfill.min.js"></script>
// Browsers have good Promise support
        require('promise/polyfill');

        var options = require('../less/default-options')();

        if (window.less) {
            for (key in window.less) {
                if (window.less.hasOwnProperty(key)) {
                    options[key] = window.less[key];
                }
            }
        }
        require('./add-default-options')(window, options);

        options.plugins = options.plugins || [];

        if (window.LESS_PLUGINS) {
            options.plugins = options.plugins.concat(window.LESS_PLUGINS);
        }

        var less = module.exports = require('./index')(window, options);

        window.less = less;

        var css, head, style;

// Always restore page visibility
        function resolveOrReject(data) {
            if (data.filename) {
                console.warn(data);
            }
            if (!options.async) {
                head.removeChild(style);
            }
        }

        if (options.onReady) {
            if (/!watch/.test(window.location.hash)) {
                less.watch();
            }
            // Simulate synchronous stylesheet loading by hiding page rendering
            if (!options.async) {
                css = 'body { display: none !important }';
                head = document.head || document.getElementsByTagName('head')[0];
                style = document.createElement('style');

                style.type = 'text/css';
                if (style.styleSheet) {
                    style.styleSheet.cssText = css;
                } else {
                    style.appendChild(document.createTextNode(css));
                }

                head.appendChild(style);
            }
            less.registerStylesheetsImmediately();
            less.pageLoadFinished = less.refresh(less.env === 'development').then(resolveOrReject, resolveOrReject);
        }

    },{"../less/default-options":17,"./add-default-options":1,"./index":8,"promise/polyfill":104}],3:[function(require,module,exports){
        var utils = require('./utils');
        module.exports = {
            createCSS: function (document, styles, sheet) {
                // Strip the query-string
                var href = sheet.href || '';

                // If there is no title set, use the filename, minus the extension
                var id = 'less:' + (sheet.title || utils.extractId(href));

                // If this has already been inserted into the DOM, we may need to replace it
                var oldStyleNode = document.getElementById(id);
                var keepOldStyleNode = false;

                // Create a new stylesheet node for insertion or (if necessary) replacement
                var styleNode = document.createElement('style');
                styleNode.setAttribute('type', 'text/css');
                if (sheet.media) {
                    styleNode.setAttribute('media', sheet.media);
                }
                styleNode.id = id;

                if (!styleNode.styleSheet) {
                    styleNode.appendChild(document.createTextNode(styles));

                    // If new contents match contents of oldStyleNode, don't replace oldStyleNode
                    keepOldStyleNode = (oldStyleNode !== null && oldStyleNode.childNodes.length > 0 && styleNode.childNodes.length > 0 &&
                        oldStyleNode.firstChild.nodeValue === styleNode.firstChild.nodeValue);
                }

                var head = document.getElementsByTagName('head')[0];

                // If there is no oldStyleNode, just append; otherwise, only append if we need
                // to replace oldStyleNode with an updated stylesheet
                if (oldStyleNode === null || keepOldStyleNode === false) {
                    var nextEl = sheet && sheet.nextSibling || null;
                    if (nextEl) {
                        nextEl.parentNode.insertBefore(styleNode, nextEl);
                    } else {
                        head.appendChild(styleNode);
                    }
                }
                if (oldStyleNode && keepOldStyleNode === false) {
                    oldStyleNode.parentNode.removeChild(oldStyleNode);
                }

                // For IE.
                // This needs to happen *after* the style element is added to the DOM, otherwise IE 7 and 8 may crash.
                // See http://social.msdn.microsoft.com/Forums/en-US/7e081b65-878a-4c22-8e68-c10d39c2ed32/internet-explorer-crashes-appending-style-element-to-head
                if (styleNode.styleSheet) {
                    try {
                        styleNode.styleSheet.cssText = styles;
                    } catch (e) {
                        throw new Error('Couldn\'t reassign styleSheet.cssText.');
                    }
                }
            },
            currentScript: function(window) {
                var document = window.document;
                return document.currentScript || (function() {
                    var scripts = document.getElementsByTagName('script');
                    return scripts[scripts.length - 1];
                })();
            }
        };

    },{"./utils":11}],4:[function(require,module,exports){
// Cache system is a bit outdated and could do with work

        module.exports = function(window, options, logger) {
            var cache = null;
            if (options.env !== 'development') {
                try {
                    cache = (typeof window.localStorage === 'undefined') ? null : window.localStorage;
                } catch (_) {}
            }
            return {
                setCSS: function(path, lastModified, modifyVars, styles) {
                    if (cache) {
                        logger.info('saving ' + path + ' to cache.');
                        try {
                            cache.setItem(path, styles);
                            cache.setItem(path + ':timestamp', lastModified);
                            if (modifyVars) {
                                cache.setItem(path + ':vars', JSON.stringify(modifyVars));
                            }
                        } catch (e) {
                            // TODO - could do with adding more robust error handling
                            logger.error('failed to save "' + path + '" to local storage for caching.');
                        }
                    }
                },
                getCSS: function(path, webInfo, modifyVars) {
                    var css       = cache && cache.getItem(path),
                        timestamp = cache && cache.getItem(path + ':timestamp'),
                        vars      = cache && cache.getItem(path + ':vars');

                    modifyVars = modifyVars || {};
                    vars = vars || "{}"; // if not set, treat as the JSON representation of an empty object

                    if (timestamp && webInfo.lastModified &&
                        (new Date(webInfo.lastModified).valueOf() ===
                            new Date(timestamp).valueOf()) &&
                        JSON.stringify(modifyVars) === vars) {
                        // Use local copy
                        return css;
                    }
                }
            };
        };

    },{}],5:[function(require,module,exports){
        var utils = require('./utils'),
            browser = require('./browser');

        module.exports = function(window, less, options) {

            function errorHTML(e, rootHref) {
                var id = 'less-error-message:' + utils.extractId(rootHref || '');
                var template = '<li><label>{line}</label><pre class="{class}">{content}</pre></li>';
                var elem = window.document.createElement('div'), timer, content, errors = [];
                var filename = e.filename || rootHref;
                var filenameNoPath = filename.match(/([^\/]+(\?.*)?)$/)[1];

                elem.id        = id;
                elem.className = 'less-error-message';

                content = '<h3>'  + (e.type || 'Syntax') + 'Error: ' + (e.message || 'There is an error in your .less file') +
                    '</h3>' + '<p>in <a href="' + filename   + '">' + filenameNoPath + '</a> ';

                var errorline = function (e, i, classname) {
                    if (e.extract[i] !== undefined) {
                        errors.push(template.replace(/\{line\}/, (parseInt(e.line, 10) || 0) + (i - 1))
                            .replace(/\{class\}/, classname)
                            .replace(/\{content\}/, e.extract[i]));
                    }
                };

                if (e.line) {
                    errorline(e, 0, '');
                    errorline(e, 1, 'line');
                    errorline(e, 2, '');
                    content += 'on line ' + e.line + ', column ' + (e.column + 1) + ':</p>' +
                        '<ul>' + errors.join('') + '</ul>';
                }
                if (e.stack && (e.extract || options.logLevel >= 4)) {
                    content += '<br/>Stack Trace</br />' + e.stack.split('\n').slice(1).join('<br/>');
                }
                elem.innerHTML = content;

                // CSS for error messages
                browser.createCSS(window.document, [
                    '.less-error-message ul, .less-error-message li {',
                    'list-style-type: none;',
                    'margin-right: 15px;',
                    'padding: 4px 0;',
                    'margin: 0;',
                    '}',
                    '.less-error-message label {',
                    'font-size: 12px;',
                    'margin-right: 15px;',
                    'padding: 4px 0;',
                    'color: #cc7777;',
                    '}',
                    '.less-error-message pre {',
                    'color: #dd6666;',
                    'padding: 4px 0;',
                    'margin: 0;',
                    'display: inline-block;',
                    '}',
                    '.less-error-message pre.line {',
                    'color: #ff0000;',
                    '}',
                    '.less-error-message h3 {',
                    'font-size: 20px;',
                    'font-weight: bold;',
                    'padding: 15px 0 5px 0;',
                    'margin: 0;',
                    '}',
                    '.less-error-message a {',
                    'color: #10a',
                    '}',
                    '.less-error-message .error {',
                    'color: red;',
                    'font-weight: bold;',
                    'padding-bottom: 2px;',
                    'border-bottom: 1px dashed red;',
                    '}'
                ].join('\n'), { title: 'error-message' });

                elem.style.cssText = [
                    'font-family: Arial, sans-serif',
                    'border: 1px solid #e00',
                    'background-color: #eee',
                    'border-radius: 5px',
                    '-webkit-border-radius: 5px',
                    '-moz-border-radius: 5px',
                    'color: #e00',
                    'padding: 15px',
                    'margin-bottom: 15px'
                ].join(';');

                if (options.env === 'development') {
                    timer = setInterval(function () {
                        var document = window.document,
                            body = document.body;
                        if (body) {
                            if (document.getElementById(id)) {
                                body.replaceChild(elem, document.getElementById(id));
                            } else {
                                body.insertBefore(elem, body.firstChild);
                            }
                            clearInterval(timer);
                        }
                    }, 10);
                }
            }

            function removeErrorHTML(path) {
                var node = window.document.getElementById('less-error-message:' + utils.extractId(path));
                if (node) {
                    node.parentNode.removeChild(node);
                }
            }

            function removeErrorConsole(path) {
                // no action
            }

            function removeError(path) {
                if (!options.errorReporting || options.errorReporting === 'html') {
                    removeErrorHTML(path);
                } else if (options.errorReporting === 'console') {
                    removeErrorConsole(path);
                } else if (typeof options.errorReporting === 'function') {
                    options.errorReporting('remove', path);
                }
            }

            function errorConsole(e, rootHref) {
                var template = '{line} {content}';
                var filename = e.filename || rootHref;
                var errors = [];
                var content = (e.type || 'Syntax') + 'Error: ' + (e.message || 'There is an error in your .less file') +
                    ' in ' + filename;

                var errorline = function (e, i, classname) {
                    if (e.extract[i] !== undefined) {
                        errors.push(template.replace(/\{line\}/, (parseInt(e.line, 10) || 0) + (i - 1))
                            .replace(/\{class\}/, classname)
                            .replace(/\{content\}/, e.extract[i]));
                    }
                };

                if (e.line) {
                    errorline(e, 0, '');
                    errorline(e, 1, 'line');
                    errorline(e, 2, '');
                    content += ' on line ' + e.line + ', column ' + (e.column + 1) + ':\n' +
                        errors.join('\n');
                }
                if (e.stack && (e.extract || options.logLevel >= 4)) {
                    content += '\nStack Trace\n' + e.stack;
                }
                less.logger.error(content);
            }

            function error(e, rootHref) {
                if (!options.errorReporting || options.errorReporting === 'html') {
                    errorHTML(e, rootHref);
                } else if (options.errorReporting === 'console') {
                    errorConsole(e, rootHref);
                } else if (typeof options.errorReporting === 'function') {
                    options.errorReporting('add', e, rootHref);
                }
            }

            return {
                add: error,
                remove: removeError
            };
        };

    },{"./browser":3,"./utils":11}],6:[function(require,module,exports){
        /* global window, XMLHttpRequest */

        module.exports = function(options, logger) {

            var AbstractFileManager = require('../less/environment/abstract-file-manager.js');

            var fileCache = {};

            // TODOS - move log somewhere. pathDiff and doing something similar in node. use pathDiff in the other browser file for the initial load
            var FileManager = function() {
            };

            FileManager.prototype = new AbstractFileManager();

            FileManager.prototype.alwaysMakePathsAbsolute = function alwaysMakePathsAbsolute() {
                return true;
            };
            FileManager.prototype.join = function join(basePath, laterPath) {
                if (!basePath) {
                    return laterPath;
                }
                return this.extractUrlParts(laterPath, basePath).path;
            };
            FileManager.prototype.doXHR = function doXHR(url, type, callback, errback) {

                var xhr = new XMLHttpRequest();
                var async = options.isFileProtocol ? options.fileAsync : true;

                if (typeof xhr.overrideMimeType === 'function') {
                    xhr.overrideMimeType('text/css');
                }
                logger.debug('XHR: Getting \'' + url + '\'');
                xhr.open('GET', url, async);
                xhr.setRequestHeader('Accept', type || 'text/x-less, text/css; q=0.9, */*; q=0.5');
                xhr.send(null);

                function handleResponse(xhr, callback, errback) {
                    if (xhr.status >= 200 && xhr.status < 300) {
                        callback(xhr.responseText,
                            xhr.getResponseHeader('Last-Modified'));
                    } else if (typeof errback === 'function') {
                        errback(xhr.status, url);
                    }
                }

                if (options.isFileProtocol && !options.fileAsync) {
                    if (xhr.status === 0 || (xhr.status >= 200 && xhr.status < 300)) {
                        callback(xhr.responseText);
                    } else {
                        errback(xhr.status, url);
                    }
                } else if (async) {
                    xhr.onreadystatechange = function () {
                        if (xhr.readyState == 4) {
                            handleResponse(xhr, callback, errback);
                        }
                    };
                } else {
                    handleResponse(xhr, callback, errback);
                }
            };
            FileManager.prototype.supports = function(filename, currentDirectory, options, environment) {
                return true;
            };

            FileManager.prototype.clearFileCache = function() {
                fileCache = {};
            };

            FileManager.prototype.loadFile = function loadFile(filename, currentDirectory, options, environment) {
                // TODO: Add prefix support like less-node?
                // What about multiple paths?

                if (currentDirectory && !this.isPathAbsolute(filename)) {
                    filename = currentDirectory + filename;
                }

                filename = options.ext ? this.tryAppendExtension(filename, options.ext) : filename;

                options = options || {};

                // sheet may be set to the stylesheet for the initial load or a collection of properties including
                // some context variables for imports
                var hrefParts = this.extractUrlParts(filename, window.location.href);
                var href      = hrefParts.url;
                var self      = this;

                return new Promise(function(resolve, reject) {
                    if (options.useFileCache && fileCache[href]) {
                        try {
                            var lessText = fileCache[href];
                            return resolve({ contents: lessText, filename: href, webInfo: { lastModified: new Date() }});
                        } catch (e) {
                            return reject({ filename: href, message: 'Error loading file ' + href + ' error was ' + e.message });
                        }
                    }

                    self.doXHR(href, options.mime, function doXHRCallback(data, lastModified) {
                        // per file cache
                        fileCache[href] = data;

                        // Use remote copy (re-parse)
                        resolve({ contents: data, filename: href, webInfo: { lastModified: lastModified }});
                    }, function doXHRError(status, url) {
                        reject({ type: 'File', message: '\'' + url + '\' wasn\'t found (' + status + ')', href: href });
                    });
                });
            };

            return FileManager;
        };

    },{"../less/environment/abstract-file-manager.js":18}],7:[function(require,module,exports){
        module.exports = function() {

            var functionRegistry = require('./../less/functions/function-registry');

            function imageSize() {
                throw {
                    type: 'Runtime',
                    message: 'Image size functions are not supported in browser version of less'
                };
            }

            var imageFunctions = {
                'image-size': function(filePathNode) {
                    imageSize(this, filePathNode);
                    return -1;
                },
                'image-width': function(filePathNode) {
                    imageSize(this, filePathNode);
                    return -1;
                },
                'image-height': function(filePathNode) {
                    imageSize(this, filePathNode);
                    return -1;
                }
            };

            functionRegistry.addMultiple(imageFunctions);
        };

    },{"./../less/functions/function-registry":27}],8:[function(require,module,exports){
//
// index.js
// Should expose the additional browser functions on to the less object
//
        var addDataAttr = require('./utils').addDataAttr,
            browser = require('./browser');

        module.exports = function(window, options) {
            var document = window.document;
            var less = require('../less')();

            less.options = options;
            var environment = less.environment,
                FileManager = require('./file-manager')(options, less.logger),
                fileManager = new FileManager();
            environment.addFileManager(fileManager);
            less.FileManager = FileManager;
            less.PluginLoader = require('./plugin-loader');

            require('./log-listener')(less, options);
            var errors = require('./error-reporting')(window, less, options);
            var cache = less.cache = options.cache || require('./cache')(window, options, less.logger);
            require('./image-size')(less.environment);

            // Setup user functions - Deprecate?
            if (options.functions) {
                less.functions.functionRegistry.addMultiple(options.functions);
            }

            var typePattern = /^text\/(x-)?less$/;

            function clone(obj) {
                var cloned = {};
                for (var prop in obj) {
                    if (obj.hasOwnProperty(prop)) {
                        cloned[prop] = obj[prop];
                    }
                }
                return cloned;
            }

            // only really needed for phantom
            function bind(func, thisArg) {
                var curryArgs = Array.prototype.slice.call(arguments, 2);
                return function() {
                    var args = curryArgs.concat(Array.prototype.slice.call(arguments, 0));
                    return func.apply(thisArg, args);
                };
            }

            function loadStyles(modifyVars) {
                var styles = document.getElementsByTagName('style'),
                    style;

                for (var i = 0; i < styles.length; i++) {
                    style = styles[i];
                    if (style.type.match(typePattern)) {
                        var instanceOptions = clone(options);
                        instanceOptions.modifyVars = modifyVars;
                        var lessText = style.innerHTML || '';
                        instanceOptions.filename = document.location.href.replace(/#.*$/, '');

                        /* jshint loopfunc:true */
                        // use closure to store current style
                        less.render(lessText, instanceOptions,
                            bind(function(style, e, result) {
                                if (e) {
                                    errors.add(e, 'inline');
                                } else {
                                    style.type = 'text/css';
                                    if (style.styleSheet) {
                                        style.styleSheet.cssText = result.css;
                                    } else {
                                        style.innerHTML = result.css;
                                    }
                                }
                            }, null, style));
                    }
                }
            }

            function loadStyleSheet(sheet, callback, reload, remaining, modifyVars) {

                var instanceOptions = clone(options);
                addDataAttr(instanceOptions, sheet);
                instanceOptions.mime = sheet.type;

                if (modifyVars) {
                    instanceOptions.modifyVars = modifyVars;
                }

                function loadInitialFileCallback(loadedFile) {

                    var data = loadedFile.contents,
                        path = loadedFile.filename,
                        webInfo = loadedFile.webInfo;

                    var newFileInfo = {
                        currentDirectory: fileManager.getPath(path),
                        filename: path,
                        rootFilename: path,
                        rewriteUrls: instanceOptions.rewriteUrls
                    };

                    newFileInfo.entryPath = newFileInfo.currentDirectory;
                    newFileInfo.rootpath = instanceOptions.rootpath || newFileInfo.currentDirectory;

                    if (webInfo) {
                        webInfo.remaining = remaining;

                        var css = cache.getCSS(path, webInfo, instanceOptions.modifyVars);
                        if (!reload && css) {
                            webInfo.local = true;
                            callback(null, css, data, sheet, webInfo, path);
                            return;
                        }

                    }

                    // TODO add tests around how this behaves when reloading
                    errors.remove(path);

                    instanceOptions.rootFileInfo = newFileInfo;
                    less.render(data, instanceOptions, function(e, result) {
                        if (e) {
                            e.href = path;
                            callback(e);
                        } else {
                            cache.setCSS(sheet.href, webInfo.lastModified, instanceOptions.modifyVars, result.css);
                            callback(null, result.css, data, sheet, webInfo, path);
                        }
                    });
                }

                fileManager.loadFile(sheet.href, null, instanceOptions, environment)
                    .then(function(loadedFile) {
                        loadInitialFileCallback(loadedFile);
                    }).catch(function(err) {
                    console.log(err);
                    callback(err);
                });

            }

            function loadStyleSheets(callback, reload, modifyVars) {
                for (var i = 0; i < less.sheets.length; i++) {
                    loadStyleSheet(less.sheets[i], callback, reload, less.sheets.length - (i + 1), modifyVars);
                }
            }

            function initRunningMode() {
                if (less.env === 'development') {
                    less.watchTimer = setInterval(function () {
                        if (less.watchMode) {
                            fileManager.clearFileCache();
                            loadStyleSheets(function (e, css, _, sheet, webInfo) {
                                if (e) {
                                    errors.add(e, e.href || sheet.href);
                                } else if (css) {
                                    browser.createCSS(window.document, css, sheet);
                                }
                            });
                        }
                    }, options.poll);
                }
            }

            //
            // Watch mode
            //
            less.watch   = function () {
                if (!less.watchMode ) {
                    less.env = 'development';
                    initRunningMode();
                }
                this.watchMode = true;
                return true;
            };

            less.unwatch = function () {clearInterval(less.watchTimer); this.watchMode = false; return false; };

            //
            // Synchronously get all <link> tags with the 'rel' attribute set to
            // "stylesheet/less".
            //
            less.registerStylesheetsImmediately = function() {
                var links = document.getElementsByTagName('link');
                less.sheets = [];

                for (var i = 0; i < links.length; i++) {
                    if (links[i].rel === 'stylesheet/less' || (links[i].rel.match(/stylesheet/) &&
                        (links[i].type.match(typePattern)))) {
                        less.sheets.push(links[i]);
                    }
                }
            };

            //
            // Asynchronously get all <link> tags with the 'rel' attribute set to
            // "stylesheet/less", returning a Promise.
            //
            less.registerStylesheets = function() {
                return new Promise(function(resolve, reject) {
                    less.registerStylesheetsImmediately();
                    resolve();
                });
            };

            //
            // With this function, it's possible to alter variables and re-render
            // CSS without reloading less-files
            //
            less.modifyVars = function(record) {
                return less.refresh(true, record, false);
            };

            less.refresh = function (reload, modifyVars, clearFileCache) {
                if ((reload || clearFileCache) && clearFileCache !== false) {
                    fileManager.clearFileCache();
                }
                return new Promise(function (resolve, reject) {
                    var startTime, endTime, totalMilliseconds, remainingSheets;
                    startTime = endTime = new Date();

                    // Set counter for remaining unprocessed sheets
                    remainingSheets = less.sheets.length;

                    if (remainingSheets === 0) {

                        endTime = new Date();
                        totalMilliseconds = endTime - startTime;
                        less.logger.info('Less has finished and no sheets were loaded.');
                        resolve({
                            startTime: startTime,
                            endTime: endTime,
                            totalMilliseconds: totalMilliseconds,
                            sheets: less.sheets.length
                        });

                    } else {
                        // Relies on less.sheets array, callback seems to be guaranteed to be called for every element of the array
                        loadStyleSheets(function (e, css, _, sheet, webInfo) {
                            if (e) {
                                errors.add(e, e.href || sheet.href);
                                reject(e);
                                return;
                            }
                            if (webInfo.local) {
                                less.logger.info('Loading ' + sheet.href + ' from cache.');
                            } else {
                                less.logger.info('Rendered ' + sheet.href + ' successfully.');
                            }
                            browser.createCSS(window.document, css, sheet);
                            less.logger.info('CSS for ' + sheet.href + ' generated in ' + (new Date() - endTime) + 'ms');

                            // Count completed sheet
                            remainingSheets--;

                            // Check if the last remaining sheet was processed and then call the promise
                            if (remainingSheets === 0) {
                                totalMilliseconds = new Date() - startTime;
                                less.logger.info('Less has finished. CSS generated in ' + totalMilliseconds + 'ms');
                                resolve({
                                    startTime: startTime,
                                    endTime: endTime,
                                    totalMilliseconds: totalMilliseconds,
                                    sheets: less.sheets.length
                                });
                            }
                            endTime = new Date();
                        }, reload, modifyVars);
                    }

                    loadStyles(modifyVars);
                });
            };

            less.refreshStyles = loadStyles;
            return less;
        };

    },{"../less":37,"./browser":3,"./cache":4,"./error-reporting":5,"./file-manager":6,"./image-size":7,"./log-listener":9,"./plugin-loader":10,"./utils":11}],9:[function(require,module,exports){
        module.exports = function(less, options) {

            var logLevel_debug = 4,
                logLevel_info = 3,
                logLevel_warn = 2,
                logLevel_error = 1;

            // The amount of logging in the javascript console.
            // 3 - Debug, information and errors
            // 2 - Information and errors
            // 1 - Errors
            // 0 - None
            // Defaults to 2
            options.logLevel = typeof options.logLevel !== 'undefined' ? options.logLevel : (options.env === 'development' ?  logLevel_info : logLevel_error);

            if (!options.loggers) {
                options.loggers = [{
                    debug: function(msg) {
                        if (options.logLevel >= logLevel_debug) {
                            console.log(msg);
                        }
                    },
                    info: function(msg) {
                        if (options.logLevel >= logLevel_info) {
                            console.log(msg);
                        }
                    },
                    warn: function(msg) {
                        if (options.logLevel >= logLevel_warn) {
                            console.warn(msg);
                        }
                    },
                    error: function(msg) {
                        if (options.logLevel >= logLevel_error) {
                            console.error(msg);
                        }
                    }
                }];
            }
            for (var i = 0; i < options.loggers.length; i++) {
                less.logger.addListener(options.loggers[i]);
            }
        };

    },{}],10:[function(require,module,exports){
// TODO: Add tests for browser @plugin
        /* global window */

        var AbstractPluginLoader = require('../less/environment/abstract-plugin-loader.js');

        /**
         * Browser Plugin Loader
         */
        var PluginLoader = function(less) {
            this.less = less;
            // Should we shim this.require for browser? Probably not?
        };

        PluginLoader.prototype = new AbstractPluginLoader();

        PluginLoader.prototype.loadPlugin = function(filename, basePath, context, environment, fileManager) {
            return new Promise(function(fulfill, reject) {
                fileManager.loadFile(filename, basePath, context, environment)
                    .then(fulfill).catch(reject);
            });
        };

        module.exports = PluginLoader;


    },{"../less/environment/abstract-plugin-loader.js":19}],11:[function(require,module,exports){
        module.exports = {
            extractId: function(href) {
                return href.replace(/^[a-z-]+:\/+?[^\/]+/, '')  // Remove protocol & domain
                    .replace(/[\?\&]livereload=\w+/, '')        // Remove LiveReload cachebuster
                    .replace(/^\//, '')                         // Remove root /
                    .replace(/\.[a-zA-Z]+$/, '')                // Remove simple extension
                    .replace(/[^\.\w-]+/g, '-')                 // Replace illegal characters
                    .replace(/\./g, ':');                       // Replace dots with colons(for valid id)
            },
            addDataAttr: function(options, tag) {
                for (var opt in tag.dataset) {
                    if (tag.dataset.hasOwnProperty(opt)) {
                        if (opt === 'env' || opt === 'dumpLineNumbers' || opt === 'rootpath' || opt === 'errorReporting') {
                            options[opt] = tag.dataset[opt];
                        } else {
                            try {
                                options[opt] = JSON.parse(tag.dataset[opt]);
                            }
                            catch (_) {}
                        }
                    }
                }
            }
        };

    },{}],12:[function(require,module,exports){
        module.exports = {
            Math: {
                ALWAYS: 0,
                PARENS_DIVISION: 1,
                PARENS: 2,
                STRICT_LEGACY: 3
            },
            RewriteUrls: {
                OFF: 0,
                LOCAL: 1,
                ALL: 2
            }
        };
    },{}],13:[function(require,module,exports){
        var contexts = {};
        module.exports = contexts;
        var Constants = require('./constants');

        var copyFromOriginal = function copyFromOriginal(original, destination, propertiesToCopy) {
            if (!original) { return; }

            for (var i = 0; i < propertiesToCopy.length; i++) {
                if (original.hasOwnProperty(propertiesToCopy[i])) {
                    destination[propertiesToCopy[i]] = original[propertiesToCopy[i]];
                }
            }
        };

        /*
 parse is used whilst parsing
 */
        var parseCopyProperties = [
            // options
            'paths',            // option - unmodified - paths to search for imports on
            'rewriteUrls',      // option - whether to adjust URL's to be relative
            'rootpath',         // option - rootpath to append to URL's
            'strictImports',    // option -
            'insecure',         // option - whether to allow imports from insecure ssl hosts
            'dumpLineNumbers',  // option - whether to dump line numbers
            'compress',         // option - whether to compress
            'syncImport',       // option - whether to import synchronously
            'chunkInput',       // option - whether to chunk input. more performant but causes parse issues.
            'mime',             // browser only - mime type for sheet import
            'useFileCache',     // browser only - whether to use the per file session cache
            // context
            'processImports',   // option & context - whether to process imports. if false then imports will not be imported.
                                // Used by the import manager to stop multiple import visitors being created.
            'pluginManager'     // Used as the plugin manager for the session
        ];

        contexts.Parse = function(options) {
            copyFromOriginal(options, this, parseCopyProperties);

            if (typeof this.paths === 'string') { this.paths = [this.paths]; }
        };

        var evalCopyProperties = [
            'paths',             // additional include paths
            'compress',          // whether to compress
            'ieCompat',          // whether to enforce IE compatibility (IE8 data-uri)
            'math',              // whether math has to be within parenthesis
            'strictUnits',       // whether units need to evaluate correctly
            'sourceMap',         // whether to output a source map
            'importMultiple',    // whether we are currently importing multiple copies
            'urlArgs',           // whether to add args into url tokens
            'javascriptEnabled', // option - whether Inline JavaScript is enabled. if undefined, defaults to false
            'pluginManager',     // Used as the plugin manager for the session
            'importantScope',    // used to bubble up !important statements
            'rewriteUrls'        // option - whether to adjust URL's to be relative
        ];

        contexts.Eval = function(options, frames) {
            copyFromOriginal(options, this, evalCopyProperties);

            if (typeof this.paths === 'string') { this.paths = [this.paths]; }

            this.frames = frames || [];
            this.importantScope = this.importantScope || [];
        };

        contexts.Eval.prototype.enterCalc = function () {
            if (!this.calcStack) {
                this.calcStack = [];
            }
            this.calcStack.push(true);
            this.inCalc = true;
        };

        contexts.Eval.prototype.exitCalc = function () {
            this.calcStack.pop();
            if (!this.calcStack) {
                this.inCalc = false;
            }
        };

        contexts.Eval.prototype.inParenthesis = function () {
            if (!this.parensStack) {
                this.parensStack = [];
            }
            this.parensStack.push(true);
        };

        contexts.Eval.prototype.outOfParenthesis = function () {
            this.parensStack.pop();
        };

        contexts.Eval.prototype.inCalc = false;
        contexts.Eval.prototype.mathOn = true;
        contexts.Eval.prototype.isMathOn = function (op) {
            if (!this.mathOn) {
                return false;
            }
            if (op === '/' && this.math !== Constants.Math.ALWAYS && (!this.parensStack || !this.parensStack.length)) {
                return false;
            }
            if (this.math > Constants.Math.PARENS_DIVISION) {
                return this.parensStack && this.parensStack.length;
            }
            return true;
        };

        contexts.Eval.prototype.pathRequiresRewrite = function (path) {
            var isRelative = this.rewriteUrls === Constants.RewriteUrls.LOCAL ? isPathLocalRelative : isPathRelative;

            return isRelative(path);
        };

        contexts.Eval.prototype.rewritePath = function (path, rootpath) {
            var newPath;

            rootpath = rootpath || '';
            newPath = this.normalizePath(rootpath + path);

            // If a path was explicit relative and the rootpath was not an absolute path
            // we must ensure that the new path is also explicit relative.
            if (isPathLocalRelative(path) &&
                isPathRelative(rootpath) &&
                isPathLocalRelative(newPath) === false) {
                newPath = './' + newPath;
            }

            return newPath;
        };

        contexts.Eval.prototype.normalizePath = function (path) {
            var
                segments = path.split('/').reverse(),
                segment;

            path = [];
            while (segments.length !== 0) {
                segment = segments.pop();
                switch ( segment ) {
                    case '.':
                        break;
                    case '..':
                        if ((path.length === 0) || (path[path.length - 1] === '..')) {
                            path.push( segment );
                        } else {
                            path.pop();
                        }
                        break;
                    default:
                        path.push(segment);
                        break;
                }
            }

            return path.join('/');
        };

        function isPathRelative(path) {
            return !/^(?:[a-z-]+:|\/|#)/i.test(path);
        }

        function isPathLocalRelative(path) {
            return path.charAt(0) === '.';
        }

// todo - do the same for the toCSS ?

    },{"./constants":12}],14:[function(require,module,exports){
        module.exports = {
            'aliceblue':'#f0f8ff',
            'antiquewhite':'#faebd7',
            'aqua':'#00ffff',
            'aquamarine':'#7fffd4',
            'azure':'#f0ffff',
            'beige':'#f5f5dc',
            'bisque':'#ffe4c4',
            'black':'#000000',
            'blanchedalmond':'#ffebcd',
            'blue':'#0000ff',
            'blueviolet':'#8a2be2',
            'brown':'#a52a2a',
            'burlywood':'#deb887',
            'cadetblue':'#5f9ea0',
            'chartreuse':'#7fff00',
            'chocolate':'#d2691e',
            'coral':'#ff7f50',
            'cornflowerblue':'#6495ed',
            'cornsilk':'#fff8dc',
            'crimson':'#dc143c',
            'cyan':'#00ffff',
            'darkblue':'#00008b',
            'darkcyan':'#008b8b',
            'darkgoldenrod':'#b8860b',
            'darkgray':'#a9a9a9',
            'darkgrey':'#a9a9a9',
            'darkgreen':'#006400',
            'darkkhaki':'#bdb76b',
            'darkmagenta':'#8b008b',
            'darkolivegreen':'#556b2f',
            'darkorange':'#ff8c00',
            'darkorchid':'#9932cc',
            'darkred':'#8b0000',
            'darksalmon':'#e9967a',
            'darkseagreen':'#8fbc8f',
            'darkslateblue':'#483d8b',
            'darkslategray':'#2f4f4f',
            'darkslategrey':'#2f4f4f',
            'darkturquoise':'#00ced1',
            'darkviolet':'#9400d3',
            'deeppink':'#ff1493',
            'deepskyblue':'#00bfff',
            'dimgray':'#696969',
            'dimgrey':'#696969',
            'dodgerblue':'#1e90ff',
            'firebrick':'#b22222',
            'floralwhite':'#fffaf0',
            'forestgreen':'#228b22',
            'fuchsia':'#ff00ff',
            'gainsboro':'#dcdcdc',
            'ghostwhite':'#f8f8ff',
            'gold':'#ffd700',
            'goldenrod':'#daa520',
            'gray':'#808080',
            'grey':'#808080',
            'green':'#008000',
            'greenyellow':'#adff2f',
            'honeydew':'#f0fff0',
            'hotpink':'#ff69b4',
            'indianred':'#cd5c5c',
            'indigo':'#4b0082',
            'ivory':'#fffff0',
            'khaki':'#f0e68c',
            'lavender':'#e6e6fa',
            'lavenderblush':'#fff0f5',
            'lawngreen':'#7cfc00',
            'lemonchiffon':'#fffacd',
            'lightblue':'#add8e6',
            'lightcoral':'#f08080',
            'lightcyan':'#e0ffff',
            'lightgoldenrodyellow':'#fafad2',
            'lightgray':'#d3d3d3',
            'lightgrey':'#d3d3d3',
            'lightgreen':'#90ee90',
            'lightpink':'#ffb6c1',
            'lightsalmon':'#ffa07a',
            'lightseagreen':'#20b2aa',
            'lightskyblue':'#87cefa',
            'lightslategray':'#778899',
            'lightslategrey':'#778899',
            'lightsteelblue':'#b0c4de',
            'lightyellow':'#ffffe0',
            'lime':'#00ff00',
            'limegreen':'#32cd32',
            'linen':'#faf0e6',
            'magenta':'#ff00ff',
            'maroon':'#800000',
            'mediumaquamarine':'#66cdaa',
            'mediumblue':'#0000cd',
            'mediumorchid':'#ba55d3',
            'mediumpurple':'#9370d8',
            'mediumseagreen':'#3cb371',
            'mediumslateblue':'#7b68ee',
            'mediumspringgreen':'#00fa9a',
            'mediumturquoise':'#48d1cc',
            'mediumvioletred':'#c71585',
            'midnightblue':'#191970',
            'mintcream':'#f5fffa',
            'mistyrose':'#ffe4e1',
            'moccasin':'#ffe4b5',
            'navajowhite':'#ffdead',
            'navy':'#000080',
            'oldlace':'#fdf5e6',
            'olive':'#808000',
            'olivedrab':'#6b8e23',
            'orange':'#ffa500',
            'orangered':'#ff4500',
            'orchid':'#da70d6',
            'palegoldenrod':'#eee8aa',
            'palegreen':'#98fb98',
            'paleturquoise':'#afeeee',
            'palevioletred':'#d87093',
            'papayawhip':'#ffefd5',
            'peachpuff':'#ffdab9',
            'peru':'#cd853f',
            'pink':'#ffc0cb',
            'plum':'#dda0dd',
            'powderblue':'#b0e0e6',
            'purple':'#800080',
            'rebeccapurple':'#663399',
            'red':'#ff0000',
            'rosybrown':'#bc8f8f',
            'royalblue':'#4169e1',
            'saddlebrown':'#8b4513',
            'salmon':'#fa8072',
            'sandybrown':'#f4a460',
            'seagreen':'#2e8b57',
            'seashell':'#fff5ee',
            'sienna':'#a0522d',
            'silver':'#c0c0c0',
            'skyblue':'#87ceeb',
            'slateblue':'#6a5acd',
            'slategray':'#708090',
            'slategrey':'#708090',
            'snow':'#fffafa',
            'springgreen':'#00ff7f',
            'steelblue':'#4682b4',
            'tan':'#d2b48c',
            'teal':'#008080',
            'thistle':'#d8bfd8',
            'tomato':'#ff6347',
            'turquoise':'#40e0d0',
            'violet':'#ee82ee',
            'wheat':'#f5deb3',
            'white':'#ffffff',
            'whitesmoke':'#f5f5f5',
            'yellow':'#ffff00',
            'yellowgreen':'#9acd32'
        };
    },{}],15:[function(require,module,exports){
        module.exports = {
            colors: require('./colors'),
            unitConversions: require('./unit-conversions')
        };

    },{"./colors":14,"./unit-conversions":16}],16:[function(require,module,exports){
        module.exports = {
            length: {
                'm': 1,
                'cm': 0.01,
                'mm': 0.001,
                'in': 0.0254,
                'px': 0.0254 / 96,
                'pt': 0.0254 / 72,
                'pc': 0.0254 / 72 * 12
            },
            duration: {
                's': 1,
                'ms': 0.001
            },
            angle: {
                'rad': 1 / (2 * Math.PI),
                'deg': 1 / 360,
                'grad': 1 / 400,
                'turn': 1
            }
        };
    },{}],17:[function(require,module,exports){
// Export a new default each time
        module.exports = function() {
            return {
                /* Inline Javascript - @plugin still allowed */
                javascriptEnabled: false,

                /* Outputs a makefile import dependency list to stdout. */
                depends: false,

                /* (DEPRECATED) Compress using less built-in compression.
         * This does an okay job but does not utilise all the tricks of
         * dedicated css compression. */
                compress: false,

                /* Runs the less parser and just reports errors without any output. */
                lint: false,

                /* Sets available include paths.
         * If the file in an @import rule does not exist at that exact location,
         * less will look for it at the location(s) passed to this option.
         * You might use this for instance to specify a path to a library which
         * you want to be referenced simply and relatively in the less files. */
                paths: [],

                /* color output in the terminal */
                color: true,

                /* The strictImports controls whether the compiler will allow an @import inside of either
         * @media blocks or (a later addition) other selector blocks.
         * See: https://github.com/less/less.js/issues/656 */
                strictImports: false,

                /* Allow Imports from Insecure HTTPS Hosts */
                insecure: false,

                /* Allows you to add a path to every generated import and url in your css.
         * This does not affect less import statements that are processed, just ones
         * that are left in the output css. */
                rootpath: '',

                /* By default URLs are kept as-is, so if you import a file in a sub-directory
         * that references an image, exactly the same URL will be output in the css.
         * This option allows you to re-write URL's in imported files so that the
         * URL is always relative to the base imported file */
                rewriteUrls: false,

                /* Compatibility with IE8. Used for limiting data-uri length */
                ieCompat: false,  // true until 3.0

                /* How to process math
         *   0 always           - eagerly try to solve all operations
         *   1 parens-division  - require parens for division "/"
         *   2 parens | strict  - require parens for all operations
         *   3 strict-legacy    - legacy strict behavior (super-strict)
         */
                math: 0,

                /* Without this option, less attempts to guess at the output unit when it does maths. */
                strictUnits: false,

                /* Effectively the declaration is put at the top of your base Less file,
         * meaning it can be used but it also can be overridden if this variable
         * is defined in the file. */
                globalVars: null,

                /* As opposed to the global variable option, this puts the declaration at the
         * end of your base file, meaning it will override anything defined in your Less file. */
                modifyVars: null,

                /* This option allows you to specify a argument to go on to every URL.  */
                urlArgs: ''
            }
        }
    },{}],18:[function(require,module,exports){
        var abstractFileManager = function() {
        };

        abstractFileManager.prototype.getPath = function (filename) {
            var j = filename.lastIndexOf('?');
            if (j > 0) {
                filename = filename.slice(0, j);
            }
            j = filename.lastIndexOf('/');
            if (j < 0) {
                j = filename.lastIndexOf('\\');
            }
            if (j < 0) {
                return '';
            }
            return filename.slice(0, j + 1);
        };

        abstractFileManager.prototype.tryAppendExtension = function(path, ext) {
            return /(\.[a-z]*$)|([\?;].*)$/.test(path) ? path : path + ext;
        };

        abstractFileManager.prototype.tryAppendLessExtension = function(path) {
            return this.tryAppendExtension(path, '.less');
        };

        abstractFileManager.prototype.supportsSync = function() {
            return false;
        };

        abstractFileManager.prototype.alwaysMakePathsAbsolute = function() {
            return false;
        };

        abstractFileManager.prototype.isPathAbsolute = function(filename) {
            return (/^(?:[a-z-]+:|\/|\\|#)/i).test(filename);
        };
// TODO: pull out / replace?
        abstractFileManager.prototype.join = function(basePath, laterPath) {
            if (!basePath) {
                return laterPath;
            }
            return basePath + laterPath;
        };

        abstractFileManager.prototype.pathDiff = function pathDiff(url, baseUrl) {
            // diff between two paths to create a relative path

            var urlParts = this.extractUrlParts(url),
                baseUrlParts = this.extractUrlParts(baseUrl),
                i, max, urlDirectories, baseUrlDirectories, diff = '';
            if (urlParts.hostPart !== baseUrlParts.hostPart) {
                return '';
            }
            max = Math.max(baseUrlParts.directories.length, urlParts.directories.length);
            for (i = 0; i < max; i++) {
                if (baseUrlParts.directories[i] !== urlParts.directories[i]) { break; }
            }
            baseUrlDirectories = baseUrlParts.directories.slice(i);
            urlDirectories = urlParts.directories.slice(i);
            for (i = 0; i < baseUrlDirectories.length - 1; i++) {
                diff += '../';
            }
            for (i = 0; i < urlDirectories.length - 1; i++) {
                diff += urlDirectories[i] + '/';
            }
            return diff;
        };
// helper function, not part of API
        abstractFileManager.prototype.extractUrlParts = function extractUrlParts(url, baseUrl) {
            // urlParts[1] = protocol://hostname/ OR /
            // urlParts[2] = / if path relative to host base
            // urlParts[3] = directories
            // urlParts[4] = filename
            // urlParts[5] = parameters

            var urlPartsRegex = /^((?:[a-z-]+:)?\/{2}(?:[^\/\?#]*\/)|([\/\\]))?((?:[^\/\\\?#]*[\/\\])*)([^\/\\\?#]*)([#\?].*)?$/i,
                urlParts = url.match(urlPartsRegex),
                returner = {}, rawDirectories = [], directories = [], i, baseUrlParts;

            if (!urlParts) {
                throw new Error('Could not parse sheet href - \'' + url + '\'');
            }

            // Stylesheets in IE don't always return the full path
            if (baseUrl && (!urlParts[1] || urlParts[2])) {
                baseUrlParts = baseUrl.match(urlPartsRegex);
                if (!baseUrlParts) {
                    throw new Error('Could not parse page url - \'' + baseUrl + '\'');
                }
                urlParts[1] = urlParts[1] || baseUrlParts[1] || '';
                if (!urlParts[2]) {
                    urlParts[3] = baseUrlParts[3] + urlParts[3];
                }
            }

            if (urlParts[3]) {
                rawDirectories = urlParts[3].replace(/\\/g, '/').split('/');

                // collapse '..' and skip '.'
                for (i = 0; i < rawDirectories.length; i++) {

                    if (rawDirectories[i] === '..') {
                        directories.pop();
                    }
                    else if (rawDirectories[i] !== '.') {
                        directories.push(rawDirectories[i]);
                    }

                }
            }

            returner.hostPart = urlParts[1];
            returner.directories = directories;
            returner.rawPath = (urlParts[1] || '') + rawDirectories.join('/');
            returner.path = (urlParts[1] || '') + directories.join('/');
            returner.filename = urlParts[4];
            returner.fileUrl = returner.path + (urlParts[4] || '');
            returner.url = returner.fileUrl + (urlParts[5] || '');
            return returner;
        };

        module.exports = abstractFileManager;

    },{}],19:[function(require,module,exports){
        var functionRegistry = require('../functions/function-registry'),
            LessError = require('../less-error');

        var AbstractPluginLoader = function() {
            // Implemented by Node.js plugin loader
            this.require = function() {
                return null;
            }
        };

        AbstractPluginLoader.prototype.evalPlugin = function(contents, context, imports, pluginOptions, fileInfo) {

            var loader,
                registry,
                pluginObj,
                localModule,
                pluginManager,
                filename,
                result;

            pluginManager = context.pluginManager;

            if (fileInfo) {
                if (typeof fileInfo === 'string') {
                    filename = fileInfo;
                }
                else {
                    filename = fileInfo.filename;
                }
            }
            var shortname = (new this.less.FileManager()).extractUrlParts(filename).filename;

            if (filename) {
                pluginObj = pluginManager.get(filename);

                if (pluginObj) {
                    result = this.trySetOptions(pluginObj, filename, shortname, pluginOptions);
                    if (result) {
                        return result;
                    }
                    try {
                        if (pluginObj.use) {
                            pluginObj.use.call(this.context, pluginObj);
                        }
                    }
                    catch (e) {
                        e.message = e.message || 'Error during @plugin call';
                        return new LessError(e, imports, filename);
                    }
                    return pluginObj;
                }
            }
            localModule = {
                exports: {},
                pluginManager: pluginManager,
                fileInfo: fileInfo
            };
            registry = functionRegistry.create();

            var registerPlugin = function(obj) {
                pluginObj = obj;
            };

            try {
                loader = new Function('module', 'require', 'registerPlugin', 'functions', 'tree', 'less', 'fileInfo', contents);
                loader(localModule, this.require(filename), registerPlugin, registry, this.less.tree, this.less, fileInfo);
            }
            catch (e) {
                return new LessError(e, imports, filename);
            }

            if (!pluginObj) {
                pluginObj = localModule.exports;
            }
            pluginObj = this.validatePlugin(pluginObj, filename, shortname);

            if (pluginObj instanceof LessError) {
                return pluginObj;
            }

            if (pluginObj) {
                pluginObj.imports = imports;
                pluginObj.filename = filename;

                // For < 3.x (or unspecified minVersion) - setOptions() before install()
                if (!pluginObj.minVersion || this.compareVersion('3.0.0', pluginObj.minVersion) < 0) {
                    result = this.trySetOptions(pluginObj, filename, shortname, pluginOptions);

                    if (result) {
                        return result;
                    }
                }

                // Run on first load
                pluginManager.addPlugin(pluginObj, fileInfo.filename, registry);
                pluginObj.functions = registry.getLocalFunctions();

                // Need to call setOptions again because the pluginObj might have functions
                result = this.trySetOptions(pluginObj, filename, shortname, pluginOptions);
                if (result) {
                    return result;
                }

                // Run every @plugin call
                try {
                    if (pluginObj.use) {
                        pluginObj.use.call(this.context, pluginObj);
                    }
                }
                catch (e) {
                    e.message = e.message || 'Error during @plugin call';
                    return new LessError(e, imports, filename);
                }

            }
            else {
                return new LessError({ message: 'Not a valid plugin' }, imports, filename);
            }

            return pluginObj;

        };

        AbstractPluginLoader.prototype.trySetOptions = function(plugin, filename, name, options) {
            if (options && !plugin.setOptions) {
                return new LessError({
                    message: 'Options have been provided but the plugin ' +
                        name + ' does not support any options.'
                });
            }
            try {
                plugin.setOptions && plugin.setOptions(options);
            }
            catch (e) {
                return new LessError(e);
            }
        };

        AbstractPluginLoader.prototype.validatePlugin = function(plugin, filename, name) {
            if (plugin) {
                // support plugins being a function
                // so that the plugin can be more usable programmatically
                if (typeof plugin === 'function') {
                    plugin = new plugin();
                }

                if (plugin.minVersion) {
                    if (this.compareVersion(plugin.minVersion, this.less.version) < 0) {
                        return new LessError({
                            message: 'Plugin ' + name + ' requires version ' +
                                this.versionToString(plugin.minVersion)
                        });
                    }
                }
                return plugin;
            }
            return null;
        };

        AbstractPluginLoader.prototype.compareVersion = function(aVersion, bVersion) {
            if (typeof aVersion === 'string') {
                aVersion = aVersion.match(/^(\d+)\.?(\d+)?\.?(\d+)?/);
                aVersion.shift();
            }
            for (var i = 0; i < aVersion.length; i++) {
                if (aVersion[i] !== bVersion[i]) {
                    return parseInt(aVersion[i]) > parseInt(bVersion[i]) ? -1 : 1;
                }
            }
            return 0;
        };
        AbstractPluginLoader.prototype.versionToString = function(version) {
            var versionString = '';
            for (var i = 0; i < version.length; i++) {
                versionString += (versionString ? '.' : '') + version[i];
            }
            return versionString;
        };
        AbstractPluginLoader.prototype.printUsage = function(plugins) {
            for (var i = 0; i < plugins.length; i++) {
                var plugin = plugins[i];
                if (plugin.printUsage) {
                    plugin.printUsage();
                }
            }
        };

        module.exports = AbstractPluginLoader;


    },{"../functions/function-registry":27,"../less-error":38}],20:[function(require,module,exports){
        /**
         * @todo Document why this abstraction exists, and the relationship between
         *       environment, file managers, and plugin manager
         */

        var logger = require('../logger');
        var environment = function(externalEnvironment, fileManagers) {
            this.fileManagers = fileManagers || [];
            externalEnvironment = externalEnvironment || {};

            var optionalFunctions = ['encodeBase64', 'mimeLookup', 'charsetLookup', 'getSourceMapGenerator'],
                requiredFunctions = [],
                functions = requiredFunctions.concat(optionalFunctions);

            for (var i = 0; i < functions.length; i++) {
                var propName = functions[i],
                    environmentFunc = externalEnvironment[propName];
                if (environmentFunc) {
                    this[propName] = environmentFunc.bind(externalEnvironment);
                } else if (i < requiredFunctions.length) {
                    this.warn('missing required function in environment - ' + propName);
                }
            }
        };

        environment.prototype.getFileManager = function (filename, currentDirectory, options, environment, isSync) {

            if (!filename) {
                logger.warn('getFileManager called with no filename.. Please report this issue. continuing.');
            }
            if (currentDirectory == null) {
                logger.warn('getFileManager called with null directory.. Please report this issue. continuing.');
            }

            var fileManagers = this.fileManagers;
            if (options.pluginManager) {
                fileManagers = [].concat(fileManagers).concat(options.pluginManager.getFileManagers());
            }
            for (var i = fileManagers.length - 1; i >= 0 ; i--) {
                var fileManager = fileManagers[i];
                if (fileManager[isSync ? 'supportsSync' : 'supports'](filename, currentDirectory, options, environment)) {
                    return fileManager;
                }
            }
            return null;
        };

        environment.prototype.addFileManager = function (fileManager) {
            this.fileManagers.push(fileManager);
        };

        environment.prototype.clearFileManagers = function () {
            this.fileManagers = [];
        };

        module.exports = environment;

    },{"../logger":39}],21:[function(require,module,exports){

        var functionRegistry = require('./function-registry'),
            Anonymous = require('../tree/anonymous'),
            Keyword = require('../tree/keyword');

        functionRegistry.addMultiple({
            boolean: function(condition) {
                return condition ? Keyword.True : Keyword.False;
            },

            'if': function(condition, trueValue, falseValue) {
                return condition ? trueValue
                    : (falseValue || new Anonymous);
            }
        });

    },{"../tree/anonymous":50,"../tree/keyword":70,"./function-registry":27}],22:[function(require,module,exports){
        var Color = require('../tree/color'),
            functionRegistry = require('./function-registry');

// Color Blending
// ref: http://www.w3.org/TR/compositing-1

        function colorBlend(mode, color1, color2) {
            var ab = color1.alpha, cb, // backdrop
                as = color2.alpha, cs, // source
                ar, cr, r = [];        // result

            ar = as + ab * (1 - as);
            for (var i = 0; i < 3; i++) {
                cb = color1.rgb[i] / 255;
                cs = color2.rgb[i] / 255;
                cr = mode(cb, cs);
                if (ar) {
                    cr = (as * cs + ab * (cb -
                        as * (cb + cs - cr))) / ar;
                }
                r[i] = cr * 255;
            }

            return new Color(r, ar);
        }

        var colorBlendModeFunctions = {
            multiply: function(cb, cs) {
                return cb * cs;
            },
            screen: function(cb, cs) {
                return cb + cs - cb * cs;
            },
            overlay: function(cb, cs) {
                cb *= 2;
                return (cb <= 1) ?
                    colorBlendModeFunctions.multiply(cb, cs) :
                    colorBlendModeFunctions.screen(cb - 1, cs);
            },
            softlight: function(cb, cs) {
                var d = 1, e = cb;
                if (cs > 0.5) {
                    e = 1;
                    d = (cb > 0.25) ? Math.sqrt(cb)
                        : ((16 * cb - 12) * cb + 4) * cb;
                }
                return cb - (1 - 2 * cs) * e * (d - cb);
            },
            hardlight: function(cb, cs) {
                return colorBlendModeFunctions.overlay(cs, cb);
            },
            difference: function(cb, cs) {
                return Math.abs(cb - cs);
            },
            exclusion: function(cb, cs) {
                return cb + cs - 2 * cb * cs;
            },

            // non-w3c functions:
            average: function(cb, cs) {
                return (cb + cs) / 2;
            },
            negation: function(cb, cs) {
                return 1 - Math.abs(cb + cs - 1);
            }
        };

        for (var f in colorBlendModeFunctions) {
            if (colorBlendModeFunctions.hasOwnProperty(f)) {
                colorBlend[f] = colorBlend.bind(null, colorBlendModeFunctions[f]);
            }
        }

        functionRegistry.addMultiple(colorBlend);

    },{"../tree/color":55,"./function-registry":27}],23:[function(require,module,exports){
        var Dimension = require('../tree/dimension'),
            Color = require('../tree/color'),
            Quoted = require('../tree/quoted'),
            Anonymous = require('../tree/anonymous'),
            functionRegistry = require('./function-registry'),
            colorFunctions;

        function clamp(val) {
            return Math.min(1, Math.max(0, val));
        }
        function hsla(origColor, hsl) {
            var color = colorFunctions.hsla(hsl.h, hsl.s, hsl.l, hsl.a);
            if (color) {
                if (origColor.value &&
                    /^(rgb|hsl)/.test(origColor.value)) {
                    color.value = origColor.value;
                } else {
                    color.value = 'rgb';
                }
                return color;
            }
        }
        function number(n) {
            if (n instanceof Dimension) {
                return parseFloat(n.unit.is('%') ? n.value / 100 : n.value);
            } else if (typeof n === 'number') {
                return n;
            } else {
                throw {
                    type: 'Argument',
                    message: 'color functions take numbers as parameters'
                };
            }
        }
        function scaled(n, size) {
            if (n instanceof Dimension && n.unit.is('%')) {
                return parseFloat(n.value * size / 100);
            } else {
                return number(n);
            }
        }
        colorFunctions = {
            rgb: function (r, g, b) {
                var color = colorFunctions.rgba(r, g, b, 1.0);
                if (color) {
                    color.value = 'rgb';
                    return color;
                }
            },
            rgba: function (r, g, b, a) {
                try {
                    if (r instanceof Color) {
                        if (g) {
                            a = number(g);
                        } else {
                            a = r.alpha;
                        }
                        return new Color(r.rgb, a, 'rgba');
                    }
                    var rgb = [r, g, b].map(function (c) { return scaled(c, 255); });
                    a = number(a);
                    return new Color(rgb, a, 'rgba');
                }
                catch (e) {}
            },
            hsl: function (h, s, l) {
                var color = colorFunctions.hsla(h, s, l, 1.0);
                if (color) {
                    color.value = 'hsl';
                    return color;
                }
            },
            hsla: function (h, s, l, a) {
                try {
                    if (h instanceof Color) {
                        if (s) {
                            a = number(s);
                        } else {
                            a = h.alpha;
                        }
                        return new Color(h.rgb, a, 'hsla');
                    }

                    var m1, m2;

                    function hue(h) {
                        h = h < 0 ? h + 1 : (h > 1 ? h - 1 : h);
                        if (h * 6 < 1) {
                            return m1 + (m2 - m1) * h * 6;
                        }
                        else if (h * 2 < 1) {
                            return m2;
                        }
                        else if (h * 3 < 2) {
                            return m1 + (m2 - m1) * (2 / 3 - h) * 6;
                        }
                        else {
                            return m1;
                        }
                    }

                    h = (number(h) % 360) / 360;
                    s = clamp(number(s)); l = clamp(number(l)); a = clamp(number(a));

                    m2 = l <= 0.5 ? l * (s + 1) : l + s - l * s;
                    m1 = l * 2 - m2;

                    var rgb = [
                        hue(h + 1 / 3) * 255,
                        hue(h)       * 255,
                        hue(h - 1 / 3) * 255
                    ];
                    a = number(a);
                    return new Color(rgb, a, 'hsla');
                }
                catch (e) {}
            },

            hsv: function(h, s, v) {
                return colorFunctions.hsva(h, s, v, 1.0);
            },

            hsva: function(h, s, v, a) {
                h = ((number(h) % 360) / 360) * 360;
                s = number(s); v = number(v); a = number(a);

                var i, f;
                i = Math.floor((h / 60) % 6);
                f = (h / 60) - i;

                var vs = [v,
                    v * (1 - s),
                    v * (1 - f * s),
                    v * (1 - (1 - f) * s)];
                var perm = [[0, 3, 1],
                    [2, 0, 1],
                    [1, 0, 3],
                    [1, 2, 0],
                    [3, 1, 0],
                    [0, 1, 2]];

                return colorFunctions.rgba(vs[perm[i][0]] * 255,
                    vs[perm[i][1]] * 255,
                    vs[perm[i][2]] * 255,
                    a);
            },

            hue: function (color) {
                return new Dimension(color.toHSL().h);
            },
            saturation: function (color) {
                return new Dimension(color.toHSL().s * 100, '%');
            },
            lightness: function (color) {
                return new Dimension(color.toHSL().l * 100, '%');
            },
            hsvhue: function(color) {
                return new Dimension(color.toHSV().h);
            },
            hsvsaturation: function (color) {
                return new Dimension(color.toHSV().s * 100, '%');
            },
            hsvvalue: function (color) {
                return new Dimension(color.toHSV().v * 100, '%');
            },
            red: function (color) {
                return new Dimension(color.rgb[0]);
            },
            green: function (color) {
                return new Dimension(color.rgb[1]);
            },
            blue: function (color) {
                return new Dimension(color.rgb[2]);
            },
            alpha: function (color) {
                return new Dimension(color.toHSL().a);
            },
            luma: function (color) {
                return new Dimension(color.luma() * color.alpha * 100, '%');
            },
            luminance: function (color) {
                var luminance =
                    (0.2126 * color.rgb[0] / 255) +
                    (0.7152 * color.rgb[1] / 255) +
                    (0.0722 * color.rgb[2] / 255);

                return new Dimension(luminance * color.alpha * 100, '%');
            },
            saturate: function (color, amount, method) {
                // filter: saturate(3.2);
                // should be kept as is, so check for color
                if (!color.rgb) {
                    return null;
                }
                var hsl = color.toHSL();

                if (typeof method !== 'undefined' && method.value === 'relative') {
                    hsl.s +=  hsl.s * amount.value / 100;
                }
                else {
                    hsl.s += amount.value / 100;
                }
                hsl.s = clamp(hsl.s);
                return hsla(color, hsl);
            },
            desaturate: function (color, amount, method) {
                var hsl = color.toHSL();

                if (typeof method !== 'undefined' && method.value === 'relative') {
                    hsl.s -=  hsl.s * amount.value / 100;
                }
                else {
                    hsl.s -= amount.value / 100;
                }
                hsl.s = clamp(hsl.s);
                return hsla(color, hsl);
            },
            lighten: function (color, amount, method) {
                var hsl = color.toHSL();

                if (typeof method !== 'undefined' && method.value === 'relative') {
                    hsl.l +=  hsl.l * amount.value / 100;
                }
                else {
                    hsl.l += amount.value / 100;
                }
                hsl.l = clamp(hsl.l);
                return hsla(color, hsl);
            },
            darken: function (color, amount, method) {
                var hsl = color.toHSL();

                if (typeof method !== 'undefined' && method.value === 'relative') {
                    hsl.l -=  hsl.l * amount.value / 100;
                }
                else {
                    hsl.l -= amount.value / 100;
                }
                hsl.l = clamp(hsl.l);
                return hsla(color, hsl);
            },
            fadein: function (color, amount, method) {
                var hsl = color.toHSL();

                if (typeof method !== 'undefined' && method.value === 'relative') {
                    hsl.a +=  hsl.a * amount.value / 100;
                }
                else {
                    hsl.a += amount.value / 100;
                }
                hsl.a = clamp(hsl.a);
                return hsla(color, hsl);
            },
            fadeout: function (color, amount, method) {
                var hsl = color.toHSL();

                if (typeof method !== 'undefined' && method.value === 'relative') {
                    hsl.a -=  hsl.a * amount.value / 100;
                }
                else {
                    hsl.a -= amount.value / 100;
                }
                hsl.a = clamp(hsl.a);
                return hsla(color, hsl);
            },
            fade: function (color, amount) {
                var hsl = color.toHSL();

                hsl.a = amount.value / 100;
                hsl.a = clamp(hsl.a);
                return hsla(color, hsl);
            },
            spin: function (color, amount) {
                var hsl = color.toHSL();
                var hue = (hsl.h + amount.value) % 360;

                hsl.h = hue < 0 ? 360 + hue : hue;

                return hsla(color, hsl);
            },
            //
            // Copyright (c) 2006-2009 Hampton Catlin, Natalie Weizenbaum, and Chris Eppstein
            // http://sass-lang.com
            //
            mix: function (color1, color2, weight) {
                if (!color1.toHSL || !color2.toHSL) {
                    console.log(color2.type);
                    console.dir(color2);
                }
                if (!weight) {
                    weight = new Dimension(50);
                }
                var p = weight.value / 100.0;
                var w = p * 2 - 1;
                var a = color1.toHSL().a - color2.toHSL().a;

                var w1 = (((w * a == -1) ? w : (w + a) / (1 + w * a)) + 1) / 2.0;
                var w2 = 1 - w1;

                var rgb = [color1.rgb[0] * w1 + color2.rgb[0] * w2,
                    color1.rgb[1] * w1 + color2.rgb[1] * w2,
                    color1.rgb[2] * w1 + color2.rgb[2] * w2];

                var alpha = color1.alpha * p + color2.alpha * (1 - p);

                return new Color(rgb, alpha);
            },
            greyscale: function (color) {
                return colorFunctions.desaturate(color, new Dimension(100));
            },
            contrast: function (color, dark, light, threshold) {
                // filter: contrast(3.2);
                // should be kept as is, so check for color
                if (!color.rgb) {
                    return null;
                }
                if (typeof light === 'undefined') {
                    light = colorFunctions.rgba(255, 255, 255, 1.0);
                }
                if (typeof dark === 'undefined') {
                    dark = colorFunctions.rgba(0, 0, 0, 1.0);
                }
                // Figure out which is actually light and dark:
                if (dark.luma() > light.luma()) {
                    var t = light;
                    light = dark;
                    dark = t;
                }
                if (typeof threshold === 'undefined') {
                    threshold = 0.43;
                } else {
                    threshold = number(threshold);
                }
                if (color.luma() < threshold) {
                    return light;
                } else {
                    return dark;
                }
            },
            // Changes made in 2.7.0 - Reverted in 3.0.0
            // contrast: function (color, color1, color2, threshold) {
            //     // Return which of `color1` and `color2` has the greatest contrast with `color`
            //     // according to the standard WCAG contrast ratio calculation.
            //     // http://www.w3.org/TR/WCAG20/#contrast-ratiodef
            //     // The threshold param is no longer used, in line with SASS.
            //     // filter: contrast(3.2);
            //     // should be kept as is, so check for color
            //     if (!color.rgb) {
            //         return null;
            //     }
            //     if (typeof color1 === 'undefined') {
            //         color1 = colorFunctions.rgba(0, 0, 0, 1.0);
            //     }
            //     if (typeof color2 === 'undefined') {
            //         color2 = colorFunctions.rgba(255, 255, 255, 1.0);
            //     }
            //     var contrast1, contrast2;
            //     var luma = color.luma();
            //     var luma1 = color1.luma();
            //     var luma2 = color2.luma();
            //     // Calculate contrast ratios for each color
            //     if (luma > luma1) {
            //         contrast1 = (luma + 0.05) / (luma1 + 0.05);
            //     } else {
            //         contrast1 = (luma1 + 0.05) / (luma + 0.05);
            //     }
            //     if (luma > luma2) {
            //         contrast2 = (luma + 0.05) / (luma2 + 0.05);
            //     } else {
            //         contrast2 = (luma2 + 0.05) / (luma + 0.05);
            //     }
            //     if (contrast1 > contrast2) {
            //         return color1;
            //     } else {
            //         return color2;
            //     }
            // },
            argb: function (color) {
                return new Anonymous(color.toARGB());
            },
            color: function(c) {
                if ((c instanceof Quoted) &&
                    (/^#([A-Fa-f0-9]{8}|[A-Fa-f0-9]{6}|[A-Fa-f0-9]{3,4})$/i.test(c.value))) {
                    var val = c.value.slice(1);
                    return new Color(val, undefined, '#' + val);
                }
                if ((c instanceof Color) || (c = Color.fromKeyword(c.value))) {
                    c.value = undefined;
                    return c;
                }
                throw {
                    type:    'Argument',
                    message: 'argument must be a color keyword or 3|4|6|8 digit hex e.g. #FFF'
                };
            },
            tint: function(color, amount) {
                return colorFunctions.mix(colorFunctions.rgb(255, 255, 255), color, amount);
            },
            shade: function(color, amount) {
                return colorFunctions.mix(colorFunctions.rgb(0, 0, 0), color, amount);
            }
        };
        functionRegistry.addMultiple(colorFunctions);

    },{"../tree/anonymous":50,"../tree/color":55,"../tree/dimension":62,"../tree/quoted":80,"./function-registry":27}],24:[function(require,module,exports){
        module.exports = function(environment) {
            var Quoted = require('../tree/quoted'),
                URL = require('../tree/url'),
                utils = require('../utils'),
                functionRegistry = require('./function-registry'),
                fallback = function(functionThis, node) {
                    return new URL(node, functionThis.index, functionThis.currentFileInfo).eval(functionThis.context);
                },
                logger = require('../logger');

            functionRegistry.add('data-uri', function(mimetypeNode, filePathNode) {

                if (!filePathNode) {
                    filePathNode = mimetypeNode;
                    mimetypeNode = null;
                }

                var mimetype = mimetypeNode && mimetypeNode.value;
                var filePath = filePathNode.value;
                var currentFileInfo = this.currentFileInfo;
                var currentDirectory = currentFileInfo.rewriteUrls ?
                    currentFileInfo.currentDirectory : currentFileInfo.entryPath;

                var fragmentStart = filePath.indexOf('#');
                var fragment = '';
                if (fragmentStart !== -1) {
                    fragment = filePath.slice(fragmentStart);
                    filePath = filePath.slice(0, fragmentStart);
                }
                var context = utils.clone(this.context);
                context.rawBuffer = true;

                var fileManager = environment.getFileManager(filePath, currentDirectory, context, environment, true);

                if (!fileManager) {
                    return fallback(this, filePathNode);
                }

                var useBase64 = false;

                // detect the mimetype if not given
                if (!mimetypeNode) {

                    mimetype = environment.mimeLookup(filePath);

                    if (mimetype === 'image/svg+xml') {
                        useBase64 = false;
                    } else {
                        // use base 64 unless it's an ASCII or UTF-8 format
                        var charset = environment.charsetLookup(mimetype);
                        useBase64 = ['US-ASCII', 'UTF-8'].indexOf(charset) < 0;
                    }
                    if (useBase64) { mimetype += ';base64'; }
                }
                else {
                    useBase64 = /;base64$/.test(mimetype);
                }

                var fileSync = fileManager.loadFileSync(filePath, currentDirectory, context, environment);
                if (!fileSync.contents) {
                    logger.warn('Skipped data-uri embedding of ' + filePath + ' because file not found');
                    return fallback(this, filePathNode || mimetypeNode);
                }
                var buf = fileSync.contents;
                if (useBase64 && !environment.encodeBase64) {
                    return fallback(this, filePathNode);
                }

                buf = useBase64 ? environment.encodeBase64(buf) : encodeURIComponent(buf);

                var uri = 'data:' + mimetype + ',' + buf + fragment;

                // IE8 cannot handle a data-uri larger than 32,768 characters. If this is exceeded
                // and the --ieCompat flag is enabled, return a normal url() instead.
                var DATA_URI_MAX = 32768;
                if (uri.length >= DATA_URI_MAX) {

                    if (this.context.ieCompat !== false) {
                        logger.warn('Skipped data-uri embedding of ' + filePath + ' because its size (' + uri.length +
                            ' characters) exceeds IE8-safe ' + DATA_URI_MAX + ' characters!');

                        return fallback(this, filePathNode || mimetypeNode);
                    }
                }

                return new URL(new Quoted('"' + uri + '"', uri, false, this.index, this.currentFileInfo), this.index, this.currentFileInfo);
            });
        };

    },{"../logger":39,"../tree/quoted":80,"../tree/url":85,"../utils":89,"./function-registry":27}],25:[function(require,module,exports){
        var Keyword = require('../tree/keyword'),
            functionRegistry = require('./function-registry');

        var defaultFunc = {
            eval: function () {
                var v = this.value_, e = this.error_;
                if (e) {
                    throw e;
                }
                if (v != null) {
                    return v ? Keyword.True : Keyword.False;
                }
            },
            value: function (v) {
                this.value_ = v;
            },
            error: function (e) {
                this.error_ = e;
            },
            reset: function () {
                this.value_ = this.error_ = null;
            }
        };

        functionRegistry.add('default', defaultFunc.eval.bind(defaultFunc));

        module.exports = defaultFunc;

    },{"../tree/keyword":70,"./function-registry":27}],26:[function(require,module,exports){
        var Expression = require('../tree/expression');

        var functionCaller = function(name, context, index, currentFileInfo) {
            this.name = name.toLowerCase();
            this.index = index;
            this.context = context;
            this.currentFileInfo = currentFileInfo;

            this.func = context.frames[0].functionRegistry.get(this.name);
        };
        functionCaller.prototype.isValid = function() {
            return Boolean(this.func);
        };

        functionCaller.prototype.call = function(args) {
            // This code is terrible and should be replaced as per this issue...
            // https://github.com/less/less.js/issues/2477
            if (Array.isArray(args)) {
                args = args.filter(function (item) {
                    if (item.type === 'Comment') {
                        return false;
                    }
                    return true;
                })
                    .map(function(item) {
                        if (item.type === 'Expression') {
                            var subNodes = item.value.filter(function (item) {
                                if (item.type === 'Comment') {
                                    return false;
                                }
                                return true;
                            });
                            if (subNodes.length === 1) {
                                return subNodes[0];
                            } else {
                                return new Expression(subNodes);
                            }
                        }
                        return item;
                    });
            }

            return this.func.apply(this, args);
        };

        module.exports = functionCaller;

    },{"../tree/expression":64}],27:[function(require,module,exports){
        function makeRegistry( base ) {
            return {
                _data: {},
                add: function(name, func) {
                    // precautionary case conversion, as later querying of
                    // the registry by function-caller uses lower case as well.
                    name = name.toLowerCase();

                    if (this._data.hasOwnProperty(name)) {
                        // TODO warn
                    }
                    this._data[name] = func;
                },
                addMultiple: function(functions) {
                    Object.keys(functions).forEach(
                        function(name) {
                            this.add(name, functions[name]);
                        }.bind(this));
                },
                get: function(name) {
                    return this._data[name] || ( base && base.get( name ));
                },
                getLocalFunctions: function() {
                    return this._data;
                },
                inherit: function() {
                    return makeRegistry( this );
                },
                create: function(base) {
                    return makeRegistry(base);
                }
            };
        }

        module.exports = makeRegistry( null );
    },{}],28:[function(require,module,exports){
        module.exports = function(environment) {
            var functions = {
                functionRegistry: require('./function-registry'),
                functionCaller: require('./function-caller')
            };

            // register functions
            require('./boolean');
            require('./default');
            require('./color');
            require('./color-blending');
            require('./data-uri')(environment);
            require('./list');
            require('./math');
            require('./number');
            require('./string');
            require('./svg')(environment);
            require('./types');

            return functions;
        };

    },{"./boolean":21,"./color":23,"./color-blending":22,"./data-uri":24,"./default":25,"./function-caller":26,"./function-registry":27,"./list":29,"./math":31,"./number":32,"./string":33,"./svg":34,"./types":35}],29:[function(require,module,exports){
        var Comment = require('../tree/comment'),
            Dimension = require('../tree/dimension'),
            Declaration = require('../tree/declaration'),
            Expression = require('../tree/expression'),
            Ruleset = require('../tree/ruleset'),
            Selector = require('../tree/selector'),
            Element = require('../tree/element'),
            functionRegistry = require('./function-registry');

        var getItemsFromNode = function(node) {
            // handle non-array values as an array of length 1
            // return 'undefined' if index is invalid
            var items = Array.isArray(node.value) ?
                node.value : Array(node);

            return items;
        };

        functionRegistry.addMultiple({
            _SELF: function(n) {
                return n;
            },
            extract: function(values, index) {
                index = index.value - 1; // (1-based index)

                return getItemsFromNode(values)[index];
            },
            length: function(values) {
                return new Dimension(getItemsFromNode(values).length);
            },
            /**
             * Creates a Less list of incremental values.
             * Modeled after Lodash's range function, also exists natively in PHP
             *
             * @param {Dimension} [start=1]
             * @param {Dimension} end  - e.g. 10 or 10px - unit is added to output
             * @param {Dimension} [step=1]
             */
            range: function(start, end, step) {
                var from, to, stepValue = 1, list = [];
                if (end) {
                    to = end;
                    from = start.value;
                    if (step) {
                        stepValue = step.value;
                    }
                }
                else {
                    from = 1;
                    to = start;
                }

                for (var i = from; i <= to.value; i += stepValue) {
                    list.push(new Dimension(i, to.unit));
                }

                return new Expression(list);
            },
            each: function(list, rs) {
                var rules = [], newRules, iterator;

                if (list.value) {
                    if (Array.isArray(list.value)) {
                        iterator = list.value;
                    } else {
                        iterator = [list.value];
                    }
                } else if (list.ruleset) {
                    iterator = list.ruleset.rules;
                } else if (list.rules) {
                    iterator = list.rules;
                } else if (Array.isArray(list)) {
                    iterator = list;
                } else {
                    iterator = [list];
                }

                var valueName = '@value',
                    keyName = '@key',
                    indexName = '@index';

                if (rs.params) {
                    valueName = rs.params[0] && rs.params[0].name;
                    keyName = rs.params[1] && rs.params[1].name;
                    indexName = rs.params[2] && rs.params[2].name;
                    rs = rs.rules;
                } else {
                    rs = rs.ruleset;
                }

                for (var i = 0; i < iterator.length; i++) {
                    var key, value, item = iterator[i];
                    if (item instanceof Declaration) {
                        key = typeof item.name === 'string' ? item.name : item.name[0].value;
                        value = item.value;
                    } else {
                        key = new Dimension(i + 1);
                        value = item;
                    }

                    if (item instanceof Comment) {
                        continue;
                    }

                    newRules = rs.rules.slice(0);
                    if (valueName) {
                        newRules.push(new Declaration(valueName,
                            value,
                            false, false, this.index, this.currentFileInfo));
                    }
                    if (indexName) {
                        newRules.push(new Declaration(indexName,
                            new Dimension(i + 1),
                            false, false, this.index, this.currentFileInfo));
                    }
                    if (keyName) {
                        newRules.push(new Declaration(keyName,
                            key,
                            false, false, this.index, this.currentFileInfo));
                    }

                    rules.push(new Ruleset([ new(Selector)([ new Element("", '&') ]) ],
                        newRules,
                        rs.strictImports,
                        rs.visibilityInfo()
                    ));
                }

                return new Ruleset([ new(Selector)([ new Element("", '&') ]) ],
                    rules,
                    rs.strictImports,
                    rs.visibilityInfo()
                ).eval(this.context);

            }
        });

    },{"../tree/comment":57,"../tree/declaration":60,"../tree/dimension":62,"../tree/element":63,"../tree/expression":64,"../tree/ruleset":81,"../tree/selector":82,"./function-registry":27}],30:[function(require,module,exports){
        var Dimension = require('../tree/dimension');

        var MathHelper = function() {
        };
        MathHelper._math = function (fn, unit, n) {
            if (!(n instanceof Dimension)) {
                throw { type: 'Argument', message: 'argument must be a number' };
            }
            if (unit == null) {
                unit = n.unit;
            } else {
                n = n.unify();
            }
            return new Dimension(fn(parseFloat(n.value)), unit);
        };
        module.exports = MathHelper;
    },{"../tree/dimension":62}],31:[function(require,module,exports){
        var functionRegistry = require('./function-registry'),
            mathHelper = require('./math-helper.js');

        var mathFunctions = {
            // name,  unit
            ceil:  null,
            floor: null,
            sqrt:  null,
            abs:   null,
            tan:   '',
            sin:   '',
            cos:   '',
            atan:  'rad',
            asin:  'rad',
            acos:  'rad'
        };

        for (var f in mathFunctions) {
            if (mathFunctions.hasOwnProperty(f)) {
                mathFunctions[f] = mathHelper._math.bind(null, Math[f], mathFunctions[f]);
            }
        }

        mathFunctions.round = function (n, f) {
            var fraction = typeof f === 'undefined' ? 0 : f.value;
            return mathHelper._math(function(num) { return num.toFixed(fraction); }, null, n);
        };

        functionRegistry.addMultiple(mathFunctions);

    },{"./function-registry":27,"./math-helper.js":30}],32:[function(require,module,exports){
        var Dimension = require('../tree/dimension'),
            Anonymous = require('../tree/anonymous'),
            functionRegistry = require('./function-registry'),
            mathHelper = require('./math-helper.js');

        var minMax = function (isMin, args) {
            args = Array.prototype.slice.call(args);
            switch (args.length) {
                case 0: throw { type: 'Argument', message: 'one or more arguments required' };
            }
            var i, j, current, currentUnified, referenceUnified, unit, unitStatic, unitClone,
                order  = [], // elems only contains original argument values.
                values = {}; // key is the unit.toString() for unified Dimension values,
            // value is the index into the order array.
            for (i = 0; i < args.length; i++) {
                current = args[i];
                if (!(current instanceof Dimension)) {
                    if (Array.isArray(args[i].value)) {
                        Array.prototype.push.apply(args, Array.prototype.slice.call(args[i].value));
                    }
                    continue;
                }
                currentUnified = current.unit.toString() === '' && unitClone !== undefined ? new Dimension(current.value, unitClone).unify() : current.unify();
                unit = currentUnified.unit.toString() === '' && unitStatic !== undefined ? unitStatic : currentUnified.unit.toString();
                unitStatic = unit !== '' && unitStatic === undefined || unit !== '' && order[0].unify().unit.toString() === '' ? unit : unitStatic;
                unitClone = unit !== '' && unitClone === undefined ? current.unit.toString() : unitClone;
                j = values[''] !== undefined && unit !== '' && unit === unitStatic ? values[''] : values[unit];
                if (j === undefined) {
                    if (unitStatic !== undefined && unit !== unitStatic) {
                        throw { type: 'Argument', message: 'incompatible types' };
                    }
                    values[unit] = order.length;
                    order.push(current);
                    continue;
                }
                referenceUnified = order[j].unit.toString() === '' && unitClone !== undefined ? new Dimension(order[j].value, unitClone).unify() : order[j].unify();
                if ( isMin && currentUnified.value < referenceUnified.value ||
                    !isMin && currentUnified.value > referenceUnified.value) {
                    order[j] = current;
                }
            }
            if (order.length == 1) {
                return order[0];
            }
            args = order.map(function (a) { return a.toCSS(this.context); }).join(this.context.compress ? ',' : ', ');
            return new Anonymous((isMin ? 'min' : 'max') + '(' + args + ')');
        };
        functionRegistry.addMultiple({
            min: function () {
                return minMax(true, arguments);
            },
            max: function () {
                return minMax(false, arguments);
            },
            convert: function (val, unit) {
                return val.convertTo(unit.value);
            },
            pi: function () {
                return new Dimension(Math.PI);
            },
            mod: function(a, b) {
                return new Dimension(a.value % b.value, a.unit);
            },
            pow: function(x, y) {
                if (typeof x === 'number' && typeof y === 'number') {
                    x = new Dimension(x);
                    y = new Dimension(y);
                } else if (!(x instanceof Dimension) || !(y instanceof Dimension)) {
                    throw { type: 'Argument', message: 'arguments must be numbers' };
                }

                return new Dimension(Math.pow(x.value, y.value), x.unit);
            },
            percentage: function (n) {
                var result = mathHelper._math(function(num) {
                    return num * 100;
                }, '%', n);

                return result;
            }
        });

    },{"../tree/anonymous":50,"../tree/dimension":62,"./function-registry":27,"./math-helper.js":30}],33:[function(require,module,exports){
        var Quoted = require('../tree/quoted'),
            Anonymous = require('../tree/anonymous'),
            JavaScript = require('../tree/javascript'),
            functionRegistry = require('./function-registry');

        functionRegistry.addMultiple({
            e: function (str) {
                return new Anonymous(str instanceof JavaScript ? str.evaluated : str.value);
            },
            escape: function (str) {
                return new Anonymous(
                    encodeURI(str.value).replace(/=/g, '%3D').replace(/:/g, '%3A').replace(/#/g, '%23').replace(/;/g, '%3B')
                        .replace(/\(/g, '%28').replace(/\)/g, '%29'));
            },
            replace: function (string, pattern, replacement, flags) {
                var result = string.value;
                replacement = (replacement.type === 'Quoted') ?
                    replacement.value : replacement.toCSS();
                result = result.replace(new RegExp(pattern.value, flags ? flags.value : ''), replacement);
                return new Quoted(string.quote || '', result, string.escaped);
            },
            '%': function (string /* arg, arg, ... */) {
                var args = Array.prototype.slice.call(arguments, 1),
                    result = string.value;

                for (var i = 0; i < args.length; i++) {
                    /* jshint loopfunc:true */
                    result = result.replace(/%[sda]/i, function(token) {
                        var value = ((args[i].type === 'Quoted') &&
                            token.match(/s/i)) ? args[i].value : args[i].toCSS();
                        return token.match(/[A-Z]$/) ? encodeURIComponent(value) : value;
                    });
                }
                result = result.replace(/%%/g, '%');
                return new Quoted(string.quote || '', result, string.escaped);
            }
        });

    },{"../tree/anonymous":50,"../tree/javascript":68,"../tree/quoted":80,"./function-registry":27}],34:[function(require,module,exports){
        module.exports = function(environment) {
            var Dimension = require('../tree/dimension'),
                Color = require('../tree/color'),
                Expression = require('../tree/expression'),
                Quoted = require('../tree/quoted'),
                URL = require('../tree/url'),
                functionRegistry = require('./function-registry');

            functionRegistry.add('svg-gradient', function(direction) {

                var stops,
                    gradientDirectionSvg,
                    gradientType = 'linear',
                    rectangleDimension = 'x="0" y="0" width="1" height="1"',
                    renderEnv = {compress: false},
                    returner,
                    directionValue = direction.toCSS(renderEnv),
                    i, color, position, positionValue, alpha;

                function throwArgumentDescriptor() {
                    throw { type: 'Argument',
                        message: 'svg-gradient expects direction, start_color [start_position], [color position,]...,' +
                            ' end_color [end_position] or direction, color list' };
                }

                if (arguments.length == 2) {
                    if (arguments[1].value.length < 2) {
                        throwArgumentDescriptor();
                    }
                    stops = arguments[1].value;
                } else if (arguments.length < 3) {
                    throwArgumentDescriptor();
                } else {
                    stops = Array.prototype.slice.call(arguments, 1);
                }

                switch (directionValue) {
                    case 'to bottom':
                        gradientDirectionSvg = 'x1="0%" y1="0%" x2="0%" y2="100%"';
                        break;
                    case 'to right':
                        gradientDirectionSvg = 'x1="0%" y1="0%" x2="100%" y2="0%"';
                        break;
                    case 'to bottom right':
                        gradientDirectionSvg = 'x1="0%" y1="0%" x2="100%" y2="100%"';
                        break;
                    case 'to top right':
                        gradientDirectionSvg = 'x1="0%" y1="100%" x2="100%" y2="0%"';
                        break;
                    case 'ellipse':
                    case 'ellipse at center':
                        gradientType = 'radial';
                        gradientDirectionSvg = 'cx="50%" cy="50%" r="75%"';
                        rectangleDimension = 'x="-50" y="-50" width="101" height="101"';
                        break;
                    default:
                        throw { type: 'Argument', message: 'svg-gradient direction must be \'to bottom\', \'to right\',' +
                                ' \'to bottom right\', \'to top right\' or \'ellipse at center\'' };
                }
                returner = '<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1 1">' +
                    '<' + gradientType + 'Gradient id="g" ' + gradientDirectionSvg + '>';

                for (i = 0; i < stops.length; i += 1) {
                    if (stops[i] instanceof Expression) {
                        color = stops[i].value[0];
                        position = stops[i].value[1];
                    } else {
                        color = stops[i];
                        position = undefined;
                    }

                    if (!(color instanceof Color) || (!((i === 0 || i + 1 === stops.length) && position === undefined) && !(position instanceof Dimension))) {
                        throwArgumentDescriptor();
                    }
                    positionValue = position ? position.toCSS(renderEnv) : i === 0 ? '0%' : '100%';
                    alpha = color.alpha;
                    returner += '<stop offset="' + positionValue + '" stop-color="' + color.toRGB() + '"' + (alpha < 1 ? ' stop-opacity="' + alpha + '"' : '') + '/>';
                }
                returner += '</' + gradientType + 'Gradient>' +
                    '<rect ' + rectangleDimension + ' fill="url(#g)" /></svg>';

                returner = encodeURIComponent(returner);

                returner = 'data:image/svg+xml,' + returner;
                return new URL(new Quoted('\'' + returner + '\'', returner, false, this.index, this.currentFileInfo), this.index, this.currentFileInfo);
            });
        };

    },{"../tree/color":55,"../tree/dimension":62,"../tree/expression":64,"../tree/quoted":80,"../tree/url":85,"./function-registry":27}],35:[function(require,module,exports){
        var Keyword = require('../tree/keyword'),
            DetachedRuleset = require('../tree/detached-ruleset'),
            Dimension = require('../tree/dimension'),
            Color = require('../tree/color'),
            Quoted = require('../tree/quoted'),
            Anonymous = require('../tree/anonymous'),
            URL = require('../tree/url'),
            Operation = require('../tree/operation'),
            functionRegistry = require('./function-registry');

        var isa = function (n, Type) {
                return (n instanceof Type) ? Keyword.True : Keyword.False;
            },
            isunit = function (n, unit) {
                if (unit === undefined) {
                    throw { type: 'Argument', message: 'missing the required second argument to isunit.' };
                }
                unit = typeof unit.value === 'string' ? unit.value : unit;
                if (typeof unit !== 'string') {
                    throw { type: 'Argument', message: 'Second argument to isunit should be a unit or a string.' };
                }
                return (n instanceof Dimension) && n.unit.is(unit) ? Keyword.True : Keyword.False;
            };

        functionRegistry.addMultiple({
            isruleset: function (n) {
                return isa(n, DetachedRuleset);
            },
            iscolor: function (n) {
                return isa(n, Color);
            },
            isnumber: function (n) {
                return isa(n, Dimension);
            },
            isstring: function (n) {
                return isa(n, Quoted);
            },
            iskeyword: function (n) {
                return isa(n, Keyword);
            },
            isurl: function (n) {
                return isa(n, URL);
            },
            ispixel: function (n) {
                return isunit(n, 'px');
            },
            ispercentage: function (n) {
                return isunit(n, '%');
            },
            isem: function (n) {
                return isunit(n, 'em');
            },
            isunit: isunit,
            unit: function (val, unit) {
                if (!(val instanceof Dimension)) {
                    throw { type: 'Argument',
                        message: 'the first argument to unit must be a number' +
                            (val instanceof Operation ? '. Have you forgotten parenthesis?' : '') };
                }
                if (unit) {
                    if (unit instanceof Keyword) {
                        unit = unit.value;
                    } else {
                        unit = unit.toCSS();
                    }
                } else {
                    unit = '';
                }
                return new Dimension(val.value, unit);
            },
            'get-unit': function (n) {
                return new Anonymous(n.unit);
            }
        });

    },{"../tree/anonymous":50,"../tree/color":55,"../tree/detached-ruleset":61,"../tree/dimension":62,"../tree/keyword":70,"../tree/operation":77,"../tree/quoted":80,"../tree/url":85,"./function-registry":27}],36:[function(require,module,exports){
        var contexts = require('./contexts'),
            Parser = require('./parser/parser'),
            LessError = require('./less-error'),
            utils = require('./utils'),
            PromiseConstructor = typeof Promise === 'undefined' ? require('promise') : Promise,
            logger = require('./logger');

        module.exports = function(environment) {

            // FileInfo = {
            //  'rewriteUrls' - option - whether to adjust URL's to be relative
            //  'filename' - full resolved filename of current file
            //  'rootpath' - path to append to normal URLs for this node
            //  'currentDirectory' - path to the current file, absolute
            //  'rootFilename' - filename of the base file
            //  'entryPath' - absolute path to the entry file
            //  'reference' - whether the file should not be output and only output parts that are referenced

            var ImportManager = function(less, context, rootFileInfo) {
                this.less = less;
                this.rootFilename = rootFileInfo.filename;
                this.paths = context.paths || [];  // Search paths, when importing
                this.contents = {};             // map - filename to contents of all the files
                this.contentsIgnoredChars = {}; // map - filename to lines at the beginning of each file to ignore
                this.mime = context.mime;
                this.error = null;
                this.context = context;
                // Deprecated? Unused outside of here, could be useful.
                this.queue = [];        // Files which haven't been imported yet
                this.files = {};        // Holds the imported parse trees.
            };

            /**
             * Add an import to be imported
             * @param path - the raw path
             * @param tryAppendExtension - whether to try appending a file extension (.less or .js if the path has no extension)
             * @param currentFileInfo - the current file info (used for instance to work out relative paths)
             * @param importOptions - import options
             * @param callback - callback for when it is imported
             */
            ImportManager.prototype.push = function (path, tryAppendExtension, currentFileInfo, importOptions, callback) {
                var importManager = this,
                    pluginLoader = this.context.pluginManager.Loader;

                this.queue.push(path);

                var fileParsedFunc = function (e, root, fullPath) {
                    importManager.queue.splice(importManager.queue.indexOf(path), 1); // Remove the path from the queue

                    var importedEqualsRoot = fullPath === importManager.rootFilename;
                    if (importOptions.optional && e) {
                        callback(null, {rules:[]}, false, null);
                        logger.info('The file ' + fullPath + ' was skipped because it was not found and the import was marked optional.');
                    }
                    else {
                        // Inline imports aren't cached here.
                        // If we start to cache them, please make sure they won't conflict with non-inline imports of the
                        // same name as they used to do before this comment and the condition below have been added.
                        if (!importManager.files[fullPath] && !importOptions.inline) {
                            importManager.files[fullPath] = { root: root, options: importOptions };
                        }
                        if (e && !importManager.error) { importManager.error = e; }
                        callback(e, root, importedEqualsRoot, fullPath);
                    }
                };

                var newFileInfo = {
                    rewriteUrls: this.context.rewriteUrls,
                    entryPath: currentFileInfo.entryPath,
                    rootpath: currentFileInfo.rootpath,
                    rootFilename: currentFileInfo.rootFilename
                };

                var fileManager = environment.getFileManager(path, currentFileInfo.currentDirectory, this.context, environment);

                if (!fileManager) {
                    fileParsedFunc({ message: 'Could not find a file-manager for ' + path });
                    return;
                }

                var loadFileCallback = function(loadedFile) {
                    var plugin,
                        resolvedFilename = loadedFile.filename,
                        contents = loadedFile.contents.replace(/^\uFEFF/, '');

                    // Pass on an updated rootpath if path of imported file is relative and file
                    // is in a (sub|sup) directory
                    //
                    // Examples:
                    // - If path of imported file is 'module/nav/nav.less' and rootpath is 'less/',
                    //   then rootpath should become 'less/module/nav/'
                    // - If path of imported file is '../mixins.less' and rootpath is 'less/',
                    //   then rootpath should become 'less/../'
                    newFileInfo.currentDirectory = fileManager.getPath(resolvedFilename);
                    if (newFileInfo.rewriteUrls) {
                        newFileInfo.rootpath = fileManager.join(
                            (importManager.context.rootpath || ''),
                            fileManager.pathDiff(newFileInfo.currentDirectory, newFileInfo.entryPath));

                        if (!fileManager.isPathAbsolute(newFileInfo.rootpath) && fileManager.alwaysMakePathsAbsolute()) {
                            newFileInfo.rootpath = fileManager.join(newFileInfo.entryPath, newFileInfo.rootpath);
                        }
                    }
                    newFileInfo.filename = resolvedFilename;

                    var newEnv = new contexts.Parse(importManager.context);

                    newEnv.processImports = false;
                    importManager.contents[resolvedFilename] = contents;

                    if (currentFileInfo.reference || importOptions.reference) {
                        newFileInfo.reference = true;
                    }

                    if (importOptions.isPlugin) {
                        plugin = pluginLoader.evalPlugin(contents, newEnv, importManager, importOptions.pluginArgs, newFileInfo);
                        if (plugin instanceof LessError) {
                            fileParsedFunc(plugin, null, resolvedFilename);
                        }
                        else {
                            fileParsedFunc(null, plugin, resolvedFilename);
                        }
                    } else if (importOptions.inline) {
                        fileParsedFunc(null, contents, resolvedFilename);
                    } else {

                        // import (multiple) parse trees apparently get altered and can't be cached.
                        // TODO: investigate why this is
                        if (importManager.files[resolvedFilename]
                            && !importManager.files[resolvedFilename].options.multiple
                            && !importOptions.multiple) {

                            fileParsedFunc(null, importManager.files[resolvedFilename].root, resolvedFilename);
                        }
                        else {
                            new Parser(newEnv, importManager, newFileInfo).parse(contents, function (e, root) {
                                fileParsedFunc(e, root, resolvedFilename);
                            });
                        }
                    }
                };
                var promise, context = utils.clone(this.context);

                if (tryAppendExtension) {
                    context.ext = importOptions.isPlugin ? '.js' : '.less';
                }

                if (importOptions.isPlugin) {
                    promise = pluginLoader.loadPlugin(path, currentFileInfo.currentDirectory, context, environment, fileManager);
                }
                else {
                    promise = fileManager.loadFile(path, currentFileInfo.currentDirectory, context, environment,
                        function(err, loadedFile) {
                            if (err) {
                                fileParsedFunc(err);
                            } else {
                                loadFileCallback(loadedFile);
                            }
                        });
                }
                if (promise) {
                    promise.then(loadFileCallback, fileParsedFunc);
                }

            };
            return ImportManager;
        };

    },{"./contexts":13,"./less-error":38,"./logger":39,"./parser/parser":44,"./utils":89,"promise":undefined}],37:[function(require,module,exports){
        module.exports = function(environment, fileManagers) {
            var SourceMapOutput, SourceMapBuilder, ParseTree, ImportManager, Environment;

            var initial = {
                version: [3, 9, 0],
                data: require('./data'),
                tree: require('./tree'),
                Environment: (Environment = require('./environment/environment')),
                AbstractFileManager: require('./environment/abstract-file-manager'),
                AbstractPluginLoader: require('./environment/abstract-plugin-loader'),
                environment: (environment = new Environment(environment, fileManagers)),
                visitors: require('./visitors'),
                Parser: require('./parser/parser'),
                functions: require('./functions')(environment),
                contexts: require('./contexts'),
                SourceMapOutput: (SourceMapOutput = require('./source-map-output')(environment)),
                SourceMapBuilder: (SourceMapBuilder = require('./source-map-builder')(SourceMapOutput, environment)),
                ParseTree: (ParseTree = require('./parse-tree')(SourceMapBuilder)),
                ImportManager: (ImportManager = require('./import-manager')(environment)),
                render: require('./render')(environment, ParseTree, ImportManager),
                parse: require('./parse')(environment, ParseTree, ImportManager),
                LessError: require('./less-error'),
                transformTree: require('./transform-tree'),
                utils: require('./utils'),
                PluginManager: require('./plugin-manager'),
                logger: require('./logger')
            };

            // Create a public API

            var ctor = function(t) {
                return function() {
                    var obj = Object.create(t.prototype);
                    t.apply(obj, Array.prototype.slice.call(arguments, 0));
                    return obj;
                };
            };
            var t, api = Object.create(initial);
            for (var n in initial.tree) {
                /* eslint guard-for-in: 0 */
                t = initial.tree[n];
                if (typeof t === 'function') {
                    api[n.toLowerCase()] = ctor(t);
                }
                else {
                    api[n] = Object.create(null);
                    for (var o in t) {
                        /* eslint guard-for-in: 0 */
                        api[n][o.toLowerCase()] = ctor(t[o]);
                    }
                }
            }

            return api;
        };

    },{"./contexts":13,"./data":15,"./environment/abstract-file-manager":18,"./environment/abstract-plugin-loader":19,"./environment/environment":20,"./functions":28,"./import-manager":36,"./less-error":38,"./logger":39,"./parse":41,"./parse-tree":40,"./parser/parser":44,"./plugin-manager":45,"./render":46,"./source-map-builder":47,"./source-map-output":48,"./transform-tree":49,"./tree":67,"./utils":89,"./visitors":93}],38:[function(require,module,exports){
        var utils = require('./utils');
        /**
         * This is a centralized class of any error that could be thrown internally (mostly by the parser).
         * Besides standard .message it keeps some additional data like a path to the file where the error
         * occurred along with line and column numbers.
         *
         * @class
         * @extends Error
         * @type {module.LessError}
         *
         * @prop {string} type
         * @prop {string} filename
         * @prop {number} index
         * @prop {number} line
         * @prop {number} column
         * @prop {number} callLine
         * @prop {number} callExtract
         * @prop {string[]} extract
         *
         * @param {Object} e              - An error object to wrap around or just a descriptive object
         * @param {Object} fileContentMap - An object with file contents in 'contents' property (like importManager) @todo - move to fileManager?
         * @param {string} [currentFilename]
         */
        var LessError = module.exports = function LessError(e, fileContentMap, currentFilename) {
            Error.call(this);

            var filename = e.filename || currentFilename;

            this.message = e.message;
            this.stack = e.stack;

            if (fileContentMap && filename) {
                var input = fileContentMap.contents[filename],
                    loc = utils.getLocation(e.index, input),
                    line = loc.line,
                    col  = loc.column,
                    callLine = e.call && utils.getLocation(e.call, input).line,
                    lines = input ? input.split('\n') : '';

                this.type = e.type || 'Syntax';
                this.filename = filename;
                this.index = e.index;
                this.line = typeof line === 'number' ? line + 1 : null;
                this.column = col;

                if (!this.line && this.stack) {
                    var found = this.stack.match(/(<anonymous>|Function):(\d+):(\d+)/);

                    if (found) {
                        if (found[2]) {
                            this.line = parseInt(found[2]) - 2;
                        }
                        if (found[3]) {
                            this.column = parseInt(found[3]);
                        }
                    }
                }

                this.callLine = callLine + 1;
                this.callExtract = lines[callLine];

                this.extract = [
                    lines[this.line - 2],
                    lines[this.line - 1],
                    lines[this.line]
                ];

            }

        };

        if (typeof Object.create === 'undefined') {
            var F = function () {};
            F.prototype = Error.prototype;
            LessError.prototype = new F();
        } else {
            LessError.prototype = Object.create(Error.prototype);
        }

        LessError.prototype.constructor = LessError;

        /**
         * An overridden version of the default Object.prototype.toString
         * which uses additional information to create a helpful message.
         *
         * @param {Object} options
         * @returns {string}
         */
        LessError.prototype.toString = function(options) {
            options = options || {};

            var message = '';
            var extract = this.extract || [];
            var error = [];
            var stylize = function (str) { return str; };
            if (options.stylize) {
                var type = typeof options.stylize;
                if (type !== 'function') {
                    throw Error('options.stylize should be a function, got a ' + type + '!');
                }
                stylize = options.stylize;
            }

            if (this.line !== null) {
                if (typeof extract[0] === 'string') {
                    error.push(stylize((this.line - 1) + ' ' + extract[0], 'grey'));
                }

                if (typeof extract[1] === 'string') {
                    var errorTxt = this.line + ' ';
                    if (extract[1]) {
                        errorTxt += extract[1].slice(0, this.column) +
                            stylize(stylize(stylize(extract[1].substr(this.column, 1), 'bold') +
                                extract[1].slice(this.column + 1), 'red'), 'inverse');
                    }
                    error.push(errorTxt);
                }

                if (typeof extract[2] === 'string') {
                    error.push(stylize((this.line + 1) + ' ' + extract[2], 'grey'));
                }
                error = error.join('\n') + stylize('', 'reset') + '\n';
            }

            message += stylize(this.type + 'Error: ' + this.message, 'red');
            if (this.filename) {
                message += stylize(' in ', 'red') + this.filename;
            }
            if (this.line) {
                message += stylize(' on line ' + this.line + ', column ' + (this.column + 1) + ':', 'grey');
            }

            message += '\n' + error;

            if (this.callLine) {
                message += stylize('from ', 'red') + (this.filename || '') + '/n';
                message += stylize(this.callLine, 'grey') + ' ' + this.callExtract + '/n';
            }

            return message;
        };

    },{"./utils":89}],39:[function(require,module,exports){
        module.exports = {
            error: function(msg) {
                this._fireEvent('error', msg);
            },
            warn: function(msg) {
                this._fireEvent('warn', msg);
            },
            info: function(msg) {
                this._fireEvent('info', msg);
            },
            debug: function(msg) {
                this._fireEvent('debug', msg);
            },
            addListener: function(listener) {
                this._listeners.push(listener);
            },
            removeListener: function(listener) {
                for (var i = 0; i < this._listeners.length; i++) {
                    if (this._listeners[i] === listener) {
                        this._listeners.splice(i, 1);
                        return;
                    }
                }
            },
            _fireEvent: function(type, msg) {
                for (var i = 0; i < this._listeners.length; i++) {
                    var logFunction = this._listeners[i][type];
                    if (logFunction) {
                        logFunction(msg);
                    }
                }
            },
            _listeners: []
        };

    },{}],40:[function(require,module,exports){
        var LessError = require('./less-error'),
            transformTree = require('./transform-tree'),
            logger = require('./logger');

        module.exports = function(SourceMapBuilder) {
            var ParseTree = function(root, imports) {
                this.root = root;
                this.imports = imports;
            };

            ParseTree.prototype.toCSS = function(options) {
                var evaldRoot, result = {}, sourceMapBuilder;
                try {
                    evaldRoot = transformTree(this.root, options);
                } catch (e) {
                    throw new LessError(e, this.imports);
                }

                try {
                    var compress = Boolean(options.compress);
                    if (compress) {
                        logger.warn('The compress option has been deprecated. We recommend you use a dedicated css minifier, for instance see less-plugin-clean-css.');
                    }

                    var toCSSOptions = {
                        compress: compress,
                        dumpLineNumbers: options.dumpLineNumbers,
                        strictUnits: Boolean(options.strictUnits),
                        numPrecision: 8};

                    if (options.sourceMap) {
                        sourceMapBuilder = new SourceMapBuilder(options.sourceMap);
                        result.css = sourceMapBuilder.toCSS(evaldRoot, toCSSOptions, this.imports);
                    } else {
                        result.css = evaldRoot.toCSS(toCSSOptions);
                    }
                } catch (e) {
                    throw new LessError(e, this.imports);
                }

                if (options.pluginManager) {
                    var postProcessors = options.pluginManager.getPostProcessors();
                    for (var i = 0; i < postProcessors.length; i++) {
                        result.css = postProcessors[i].process(result.css, { sourceMap: sourceMapBuilder, options: options, imports: this.imports });
                    }
                }
                if (options.sourceMap) {
                    result.map = sourceMapBuilder.getExternalSourceMap();
                }

                result.imports = [];
                for (var file in this.imports.files) {
                    if (this.imports.files.hasOwnProperty(file) && file !== this.imports.rootFilename) {
                        result.imports.push(file);
                    }
                }
                return result;
            };
            return ParseTree;
        };

    },{"./less-error":38,"./logger":39,"./transform-tree":49}],41:[function(require,module,exports){
        var PromiseConstructor,
            contexts = require('./contexts'),
            Parser = require('./parser/parser'),
            PluginManager = require('./plugin-manager'),
            LessError = require('./less-error'),
            utils = require('./utils');

        module.exports = function(environment, ParseTree, ImportManager) {
            var parse = function (input, options, callback) {

                if (typeof options === 'function') {
                    callback = options;
                    options = utils.copyOptions(this.options, {});
                }
                else {
                    options = utils.copyOptions(this.options, options || {});
                }

                if (!callback) {
                    if (!PromiseConstructor) {
                        PromiseConstructor = typeof Promise === 'undefined' ? require('promise') : Promise;
                    }
                    var self = this;
                    return new PromiseConstructor(function (resolve, reject) {
                        parse.call(self, input, options, function(err, output) {
                            if (err) {
                                reject(err);
                            } else {
                                resolve(output);
                            }
                        });
                    });
                } else {
                    var context,
                        rootFileInfo,
                        pluginManager = new PluginManager(this, !options.reUsePluginManager);

                    options.pluginManager = pluginManager;

                    context = new contexts.Parse(options);

                    if (options.rootFileInfo) {
                        rootFileInfo = options.rootFileInfo;
                    } else {
                        var filename = options.filename || 'input';
                        var entryPath = filename.replace(/[^\/\\]*$/, '');
                        rootFileInfo = {
                            filename: filename,
                            rewriteUrls: context.rewriteUrls,
                            rootpath: context.rootpath || '',
                            currentDirectory: entryPath,
                            entryPath: entryPath,
                            rootFilename: filename
                        };
                        // add in a missing trailing slash
                        if (rootFileInfo.rootpath && rootFileInfo.rootpath.slice(-1) !== '/') {
                            rootFileInfo.rootpath += '/';
                        }
                    }

                    var imports = new ImportManager(this, context, rootFileInfo);
                    this.importManager = imports;

                    // TODO: allow the plugins to be just a list of paths or names
                    // Do an async plugin queue like lessc

                    if (options.plugins) {
                        options.plugins.forEach(function(plugin) {
                            var evalResult, contents;
                            if (plugin.fileContent) {
                                contents = plugin.fileContent.replace(/^\uFEFF/, '');
                                evalResult = pluginManager.Loader.evalPlugin(contents, context, imports, plugin.options, plugin.filename);
                                if (evalResult instanceof LessError) {
                                    return callback(evalResult);
                                }
                            }
                            else {
                                pluginManager.addPlugin(plugin);
                            }
                        });
                    }

                    new Parser(context, imports, rootFileInfo)
                        .parse(input, function (e, root) {
                            if (e) { return callback(e); }
                            callback(null, root, imports, options);
                        }, options);
                }
            };
            return parse;
        };

    },{"./contexts":13,"./less-error":38,"./parser/parser":44,"./plugin-manager":45,"./utils":89,"promise":undefined}],42:[function(require,module,exports){
// Split the input into chunks.
        module.exports = function (input, fail) {
            var len = input.length, level = 0, parenLevel = 0,
                lastOpening, lastOpeningParen, lastMultiComment, lastMultiCommentEndBrace,
                chunks = [], emitFrom = 0,
                chunkerCurrentIndex, currentChunkStartIndex, cc, cc2, matched;

            function emitChunk(force) {
                var len = chunkerCurrentIndex - emitFrom;
                if (((len < 512) && !force) || !len) {
                    return;
                }
                chunks.push(input.slice(emitFrom, chunkerCurrentIndex + 1));
                emitFrom = chunkerCurrentIndex + 1;
            }

            for (chunkerCurrentIndex = 0; chunkerCurrentIndex < len; chunkerCurrentIndex++) {
                cc = input.charCodeAt(chunkerCurrentIndex);
                if (((cc >= 97) && (cc <= 122)) || (cc < 34)) {
                    // a-z or whitespace
                    continue;
                }

                switch (cc) {
                    case 40:                        // (
                        parenLevel++;
                        lastOpeningParen = chunkerCurrentIndex;
                        continue;
                    case 41:                        // )
                        if (--parenLevel < 0) {
                            return fail('missing opening `(`', chunkerCurrentIndex);
                        }
                        continue;
                    case 59:                        // ;
                        if (!parenLevel) { emitChunk(); }
                        continue;
                    case 123:                       // {
                        level++;
                        lastOpening = chunkerCurrentIndex;
                        continue;
                    case 125:                       // }
                        if (--level < 0) {
                            return fail('missing opening `{`', chunkerCurrentIndex);
                        }
                        if (!level && !parenLevel) { emitChunk(); }
                        continue;
                    case 92:                        // \
                        if (chunkerCurrentIndex < len - 1) { chunkerCurrentIndex++; continue; }
                        return fail('unescaped `\\`', chunkerCurrentIndex);
                    case 34:
                    case 39:
                    case 96:                        // ", ' and `
                        matched = 0;
                        currentChunkStartIndex = chunkerCurrentIndex;
                        for (chunkerCurrentIndex = chunkerCurrentIndex + 1; chunkerCurrentIndex < len; chunkerCurrentIndex++) {
                            cc2 = input.charCodeAt(chunkerCurrentIndex);
                            if (cc2 > 96) { continue; }
                            if (cc2 == cc) { matched = 1; break; }
                            if (cc2 == 92) {        // \
                                if (chunkerCurrentIndex == len - 1) {
                                    return fail('unescaped `\\`', chunkerCurrentIndex);
                                }
                                chunkerCurrentIndex++;
                            }
                        }
                        if (matched) { continue; }
                        return fail('unmatched `' + String.fromCharCode(cc) + '`', currentChunkStartIndex);
                    case 47:                        // /, check for comment
                        if (parenLevel || (chunkerCurrentIndex == len - 1)) { continue; }
                        cc2 = input.charCodeAt(chunkerCurrentIndex + 1);
                        if (cc2 == 47) {
                            // //, find lnfeed
                            for (chunkerCurrentIndex = chunkerCurrentIndex + 2; chunkerCurrentIndex < len; chunkerCurrentIndex++) {
                                cc2 = input.charCodeAt(chunkerCurrentIndex);
                                if ((cc2 <= 13) && ((cc2 == 10) || (cc2 == 13))) { break; }
                            }
                        } else if (cc2 == 42) {
                            // /*, find */
                            lastMultiComment = currentChunkStartIndex = chunkerCurrentIndex;
                            for (chunkerCurrentIndex = chunkerCurrentIndex + 2; chunkerCurrentIndex < len - 1; chunkerCurrentIndex++) {
                                cc2 = input.charCodeAt(chunkerCurrentIndex);
                                if (cc2 == 125) { lastMultiCommentEndBrace = chunkerCurrentIndex; }
                                if (cc2 != 42) { continue; }
                                if (input.charCodeAt(chunkerCurrentIndex + 1) == 47) { break; }
                            }
                            if (chunkerCurrentIndex == len - 1) {
                                return fail('missing closing `*/`', currentChunkStartIndex);
                            }
                            chunkerCurrentIndex++;
                        }
                        continue;
                    case 42:                       // *, check for unmatched */
                        if ((chunkerCurrentIndex < len - 1) && (input.charCodeAt(chunkerCurrentIndex + 1) == 47)) {
                            return fail('unmatched `/*`', chunkerCurrentIndex);
                        }
                        continue;
                }
            }

            if (level !== 0) {
                if ((lastMultiComment > lastOpening) && (lastMultiCommentEndBrace > lastMultiComment)) {
                    return fail('missing closing `}` or `*/`', lastOpening);
                } else {
                    return fail('missing closing `}`', lastOpening);
                }
            } else if (parenLevel !== 0) {
                return fail('missing closing `)`', lastOpeningParen);
            }

            emitChunk(true);
            return chunks;
        };

    },{}],43:[function(require,module,exports){
        var chunker = require('./chunker');

        module.exports = function() {
            var input,       // Less input string
                j,           // current chunk
                saveStack = [],   // holds state for backtracking
                furthest,    // furthest index the parser has gone to
                furthestPossibleErrorMessage, // if this is furthest we got to, this is the probably cause
                chunks,      // chunkified input
                current,     // current chunk
                currentPos,  // index of current chunk, in `input`
                parserInput = {};

            var CHARCODE_SPACE = 32,
                CHARCODE_TAB = 9,
                CHARCODE_LF = 10,
                CHARCODE_CR = 13,
                CHARCODE_PLUS = 43,
                CHARCODE_COMMA = 44,
                CHARCODE_FORWARD_SLASH = 47,
                CHARCODE_9 = 57;

            function skipWhitespace(length) {
                var oldi = parserInput.i, oldj = j,
                    curr = parserInput.i - currentPos,
                    endIndex = parserInput.i + current.length - curr,
                    mem = (parserInput.i += length),
                    inp = input,
                    c, nextChar, comment;

                for (; parserInput.i < endIndex; parserInput.i++) {
                    c = inp.charCodeAt(parserInput.i);

                    if (parserInput.autoCommentAbsorb && c === CHARCODE_FORWARD_SLASH) {
                        nextChar = inp.charAt(parserInput.i + 1);
                        if (nextChar === '/') {
                            comment = {index: parserInput.i, isLineComment: true};
                            var nextNewLine = inp.indexOf('\n', parserInput.i + 2);
                            if (nextNewLine < 0) {
                                nextNewLine = endIndex;
                            }
                            parserInput.i = nextNewLine;
                            comment.text = inp.substr(comment.index, parserInput.i - comment.index);
                            parserInput.commentStore.push(comment);
                            continue;
                        } else if (nextChar === '*') {
                            var nextStarSlash = inp.indexOf('*/', parserInput.i + 2);
                            if (nextStarSlash >= 0) {
                                comment = {
                                    index: parserInput.i,
                                    text: inp.substr(parserInput.i, nextStarSlash + 2 - parserInput.i),
                                    isLineComment: false
                                };
                                parserInput.i += comment.text.length - 1;
                                parserInput.commentStore.push(comment);
                                continue;
                            }
                        }
                        break;
                    }

                    if ((c !== CHARCODE_SPACE) && (c !== CHARCODE_LF) && (c !== CHARCODE_TAB) && (c !== CHARCODE_CR)) {
                        break;
                    }
                }

                current = current.slice(length + parserInput.i - mem + curr);
                currentPos = parserInput.i;

                if (!current.length) {
                    if (j < chunks.length - 1) {
                        current = chunks[++j];
                        skipWhitespace(0); // skip space at the beginning of a chunk
                        return true; // things changed
                    }
                    parserInput.finished = true;
                }

                return oldi !== parserInput.i || oldj !== j;
            }

            parserInput.save = function() {
                currentPos = parserInput.i;
                saveStack.push( { current: current, i: parserInput.i, j: j });
            };
            parserInput.restore = function(possibleErrorMessage) {

                if (parserInput.i > furthest || (parserInput.i === furthest && possibleErrorMessage && !furthestPossibleErrorMessage)) {
                    furthest = parserInput.i;
                    furthestPossibleErrorMessage = possibleErrorMessage;
                }
                var state = saveStack.pop();
                current = state.current;
                currentPos = parserInput.i = state.i;
                j = state.j;
            };
            parserInput.forget = function() {
                saveStack.pop();
            };
            parserInput.isWhitespace = function (offset) {
                var pos = parserInput.i + (offset || 0),
                    code = input.charCodeAt(pos);
                return (code === CHARCODE_SPACE || code === CHARCODE_CR || code === CHARCODE_TAB || code === CHARCODE_LF);
            };

            // Specialization of $(tok)
            parserInput.$re = function(tok) {
                if (parserInput.i > currentPos) {
                    current = current.slice(parserInput.i - currentPos);
                    currentPos = parserInput.i;
                }

                var m = tok.exec(current);
                if (!m) {
                    return null;
                }

                skipWhitespace(m[0].length);
                if (typeof m === 'string') {
                    return m;
                }

                return m.length === 1 ? m[0] : m;
            };

            parserInput.$char = function(tok) {
                if (input.charAt(parserInput.i) !== tok) {
                    return null;
                }
                skipWhitespace(1);
                return tok;
            };

            parserInput.$str = function(tok) {
                var tokLength = tok.length;

                // https://jsperf.com/string-startswith/21
                for (var i = 0; i < tokLength; i++) {
                    if (input.charAt(parserInput.i + i) !== tok.charAt(i)) {
                        return null;
                    }
                }

                skipWhitespace(tokLength);
                return tok;
            };

            parserInput.$quoted = function(loc) {
                var pos = loc || parserInput.i,
                    startChar = input.charAt(pos);

                if (startChar !== '\'' && startChar !== '"') {
                    return;
                }
                var length = input.length,
                    currentPosition = pos;

                for (var i = 1; i + currentPosition < length; i++) {
                    var nextChar = input.charAt(i + currentPosition);
                    switch (nextChar) {
                        case '\\':
                            i++;
                            continue;
                        case '\r':
                        case '\n':
                            break;
                        case startChar:
                            var str = input.substr(currentPosition, i + 1);
                            if (!loc && loc !== 0) {
                                skipWhitespace(i + 1);
                                return str
                            }
                            return [startChar, str];
                        default:
                    }
                }
                return null;
            };

            /**
             * Permissive parsing. Ignores everything except matching {} [] () and quotes
             * until matching token (outside of blocks)
             */
            parserInput.$parseUntil = function(tok) {
                var quote = '',
                    returnVal = null,
                    inComment = false,
                    blockDepth = 0,
                    blockStack = [],
                    parseGroups = [],
                    length = input.length,
                    startPos = parserInput.i,
                    lastPos = parserInput.i,
                    i = parserInput.i,
                    loop = true,
                    testChar;

                if (typeof tok === 'string') {
                    testChar = function(char) {
                        return char === tok;
                    }
                } else {
                    testChar = function(char) {
                        return tok.test(char);
                    }
                }

                do {
                    var prevChar, nextChar = input.charAt(i);
                    if (blockDepth === 0 && testChar(nextChar)) {
                        returnVal = input.substr(lastPos, i - lastPos);
                        if (returnVal) {
                            parseGroups.push(returnVal);
                        }
                        else {
                            parseGroups.push(' ');
                        }
                        returnVal = parseGroups;
                        skipWhitespace(i - startPos);
                        loop = false
                    } else {
                        if (inComment) {
                            if (nextChar === '*' &&
                                input.charAt(i + 1) === '/') {
                                i++;
                                blockDepth--;
                                inComment = false;
                            }
                            i++;
                            continue;
                        }
                        switch (nextChar) {
                            case '\\':
                                i++;
                                nextChar = input.charAt(i);
                                parseGroups.push(input.substr(lastPos, i - lastPos + 1));
                                lastPos = i + 1;
                                break;
                            case '/':
                                if (input.charAt(i + 1) === '*') {
                                    i++;
                                    inComment = true;
                                    blockDepth++;
                                }
                                break;
                            case '\'':
                            case '"':
                                quote = parserInput.$quoted(i);
                                if (quote) {
                                    parseGroups.push(input.substr(lastPos, i - lastPos), quote);
                                    i += quote[1].length - 1;
                                    lastPos = i + 1;
                                }
                                else {
                                    skipWhitespace(i - startPos);
                                    returnVal = nextChar;
                                    loop = false;
                                }
                                break;
                            case '{':
                                blockStack.push('}');
                                blockDepth++;
                                break;
                            case '(':
                                blockStack.push(')');
                                blockDepth++;
                                break;
                            case '[':
                                blockStack.push(']');
                                blockDepth++;
                                break;
                            case '}':
                            case ')':
                            case ']':
                                var expected = blockStack.pop();
                                if (nextChar === expected) {
                                    blockDepth--;
                                } else {
                                    // move the parser to the error and return expected
                                    skipWhitespace(i - startPos);
                                    returnVal = expected;
                                    loop = false;
                                }
                        }
                        i++;
                        if (i > length) {
                            loop = false;
                        }
                    }
                    prevChar = nextChar;
                } while (loop);

                return returnVal ? returnVal : null;
            }

            parserInput.autoCommentAbsorb = true;
            parserInput.commentStore = [];
            parserInput.finished = false;

            // Same as $(), but don't change the state of the parser,
            // just return the match.
            parserInput.peek = function(tok) {
                if (typeof tok === 'string') {
                    // https://jsperf.com/string-startswith/21
                    for (var i = 0; i < tok.length; i++) {
                        if (input.charAt(parserInput.i + i) !== tok.charAt(i)) {
                            return false;
                        }
                    }
                    return true;
                } else {
                    return tok.test(current);
                }
            };

            // Specialization of peek()
            // TODO remove or change some currentChar calls to peekChar
            parserInput.peekChar = function(tok) {
                return input.charAt(parserInput.i) === tok;
            };

            parserInput.currentChar = function() {
                return input.charAt(parserInput.i);
            };

            parserInput.prevChar = function() {
                return input.charAt(parserInput.i - 1);
            };

            parserInput.getInput = function() {
                return input;
            };

            parserInput.peekNotNumeric = function() {
                var c = input.charCodeAt(parserInput.i);
                // Is the first char of the dimension 0-9, '.', '+' or '-'
                return (c > CHARCODE_9 || c < CHARCODE_PLUS) || c === CHARCODE_FORWARD_SLASH || c === CHARCODE_COMMA;
            };

            parserInput.start = function(str, chunkInput, failFunction) {
                input = str;
                parserInput.i = j = currentPos = furthest = 0;

                // chunking apparently makes things quicker (but my tests indicate
                // it might actually make things slower in node at least)
                // and it is a non-perfect parse - it can't recognise
                // unquoted urls, meaning it can't distinguish comments
                // meaning comments with quotes or {}() in them get 'counted'
                // and then lead to parse errors.
                // In addition if the chunking chunks in the wrong place we might
                // not be able to parse a parser statement in one go
                // this is officially deprecated but can be switched on via an option
                // in the case it causes too much performance issues.
                if (chunkInput) {
                    chunks = chunker(str, failFunction);
                } else {
                    chunks = [str];
                }

                current = chunks[0];

                skipWhitespace(0);
            };

            parserInput.end = function() {
                var message,
                    isFinished = parserInput.i >= input.length;

                if (parserInput.i < furthest) {
                    message = furthestPossibleErrorMessage;
                    parserInput.i = furthest;
                }
                return {
                    isFinished: isFinished,
                    furthest: parserInput.i,
                    furthestPossibleErrorMessage: message,
                    furthestReachedEnd: parserInput.i >= input.length - 1,
                    furthestChar: input[parserInput.i]
                };
            };

            return parserInput;
        };

    },{"./chunker":42}],44:[function(require,module,exports){
        var LessError = require('../less-error'),
            tree = require('../tree'),
            visitors = require('../visitors'),
            getParserInput = require('./parser-input'),
            utils = require('../utils'),
            functionRegistry = require('../functions/function-registry');

//
// less.js - parser
//
//    A relatively straight-forward predictive parser.
//    There is no tokenization/lexing stage, the input is parsed
//    in one sweep.
//
//    To make the parser fast enough to run in the browser, several
//    optimization had to be made:
//
//    - Matching and slicing on a huge input is often cause of slowdowns.
//      The solution is to chunkify the input into smaller strings.
//      The chunks are stored in the `chunks` var,
//      `j` holds the current chunk index, and `currentPos` holds
//      the index of the current chunk in relation to `input`.
//      This gives us an almost 4x speed-up.
//
//    - In many cases, we don't need to match individual tokens;
//      for example, if a value doesn't hold any variables, operations
//      or dynamic references, the parser can effectively 'skip' it,
//      treating it as a literal.
//      An example would be '1px solid #000' - which evaluates to itself,
//      we don't need to know what the individual components are.
//      The drawback, of course is that you don't get the benefits of
//      syntax-checking on the CSS. This gives us a 50% speed-up in the parser,
//      and a smaller speed-up in the code-gen.
//
//
//    Token matching is done with the `$` function, which either takes
//    a terminal string or regexp, or a non-terminal function to call.
//    It also takes care of moving all the indices forwards.
//

        var Parser = function Parser(context, imports, fileInfo) {
            var parsers,
                parserInput = getParserInput();

            function error(msg, type) {
                throw new LessError(
                    {
                        index: parserInput.i,
                        filename: fileInfo.filename,
                        type: type || 'Syntax',
                        message: msg
                    },
                    imports
                );
            }

            function expect(arg, msg) {
                // some older browsers return typeof 'function' for RegExp
                var result = (arg instanceof Function) ? arg.call(parsers) : parserInput.$re(arg);
                if (result) {
                    return result;
                }

                error(msg || (typeof arg === 'string'
                    ? 'expected \'' + arg + '\' got \'' + parserInput.currentChar() + '\''
                    : 'unexpected token'));
            }

            // Specialization of expect()
            function expectChar(arg, msg) {
                if (parserInput.$char(arg)) {
                    return arg;
                }
                error(msg || 'expected \'' + arg + '\' got \'' + parserInput.currentChar() + '\'');
            }

            function getDebugInfo(index) {
                var filename = fileInfo.filename;

                return {
                    lineNumber: utils.getLocation(index, parserInput.getInput()).line + 1,
                    fileName: filename
                };
            }

            /**
             *  Used after initial parsing to create nodes on the fly
             *
             *  @param {String} str          - string to parse
             *  @param {Array}  parseList    - array of parsers to run input through e.g. ["value", "important"]
             *  @param {Number} currentIndex - start number to begin indexing
             *  @param {Object} fileInfo     - fileInfo to attach to created nodes
             */
            function parseNode(str, parseList, currentIndex, fileInfo, callback) {
                var result, returnNodes = [];
                var parser = parserInput;

                try {
                    parser.start(str, false, function fail(msg, index) {
                        callback({
                            message: msg,
                            index: index + currentIndex
                        });
                    });
                    for (var x = 0, p, i; (p = parseList[x]); x++) {
                        i = parser.i;
                        result = parsers[p]();
                        if (result) {
                            result._index = i + currentIndex;
                            result._fileInfo = fileInfo;
                            returnNodes.push(result);
                        }
                        else {
                            returnNodes.push(null);
                        }
                    }

                    var endInfo = parser.end();
                    if (endInfo.isFinished) {
                        callback(null, returnNodes);
                    }
                    else {
                        callback(true, null);
                    }
                } catch (e) {
                    throw new LessError({
                        index: e.index + currentIndex,
                        message: e.message
                    }, imports, fileInfo.filename);
                }
            }

            //
            // The Parser
            //
            return {
                parserInput: parserInput,
                imports: imports,
                fileInfo: fileInfo,
                parseNode: parseNode,
                //
                // Parse an input string into an abstract syntax tree,
                // @param str A string containing 'less' markup
                // @param callback call `callback` when done.
                // @param [additionalData] An optional map which can contains vars - a map (key, value) of variables to apply
                //
                parse: function (str, callback, additionalData) {
                    var root, error = null, globalVars, modifyVars, ignored, preText = '';

                    globalVars = (additionalData && additionalData.globalVars) ? Parser.serializeVars(additionalData.globalVars) + '\n' : '';
                    modifyVars = (additionalData && additionalData.modifyVars) ? '\n' + Parser.serializeVars(additionalData.modifyVars) : '';

                    if (context.pluginManager) {
                        var preProcessors = context.pluginManager.getPreProcessors();
                        for (var i = 0; i < preProcessors.length; i++) {
                            str = preProcessors[i].process(str, { context: context, imports: imports, fileInfo: fileInfo });
                        }
                    }

                    if (globalVars || (additionalData && additionalData.banner)) {
                        preText = ((additionalData && additionalData.banner) ? additionalData.banner : '') + globalVars;
                        ignored = imports.contentsIgnoredChars;
                        ignored[fileInfo.filename] = ignored[fileInfo.filename] || 0;
                        ignored[fileInfo.filename] += preText.length;
                    }

                    str = str.replace(/\r\n?/g, '\n');
                    // Remove potential UTF Byte Order Mark
                    str = preText + str.replace(/^\uFEFF/, '') + modifyVars;
                    imports.contents[fileInfo.filename] = str;

                    // Start with the primary rule.
                    // The whole syntax tree is held under a Ruleset node,
                    // with the `root` property set to true, so no `{}` are
                    // output. The callback is called when the input is parsed.
                    try {
                        parserInput.start(str, context.chunkInput, function fail(msg, index) {
                            throw new LessError({
                                index: index,
                                type: 'Parse',
                                message: msg,
                                filename: fileInfo.filename
                            }, imports);
                        });

                        tree.Node.prototype.parse = this;
                        root = new tree.Ruleset(null, this.parsers.primary());
                        tree.Node.prototype.rootNode = root;
                        root.root = true;
                        root.firstRoot = true;
                        root.functionRegistry = functionRegistry.inherit();

                    } catch (e) {
                        return callback(new LessError(e, imports, fileInfo.filename));
                    }

                    // If `i` is smaller than the `input.length - 1`,
                    // it means the parser wasn't able to parse the whole
                    // string, so we've got a parsing error.
                    //
                    // We try to extract a \n delimited string,
                    // showing the line where the parse error occurred.
                    // We split it up into two parts (the part which parsed,
                    // and the part which didn't), so we can color them differently.
                    var endInfo = parserInput.end();
                    if (!endInfo.isFinished) {

                        var message = endInfo.furthestPossibleErrorMessage;

                        if (!message) {
                            message = 'Unrecognised input';
                            if (endInfo.furthestChar === '}') {
                                message += '. Possibly missing opening \'{\'';
                            } else if (endInfo.furthestChar === ')') {
                                message += '. Possibly missing opening \'(\'';
                            } else if (endInfo.furthestReachedEnd) {
                                message += '. Possibly missing something';
                            }
                        }

                        error = new LessError({
                            type: 'Parse',
                            message: message,
                            index: endInfo.furthest,
                            filename: fileInfo.filename
                        }, imports);
                    }

                    var finish = function (e) {
                        e = error || e || imports.error;

                        if (e) {
                            if (!(e instanceof LessError)) {
                                e = new LessError(e, imports, fileInfo.filename);
                            }

                            return callback(e);
                        }
                        else {
                            return callback(null, root);
                        }
                    };

                    if (context.processImports !== false) {
                        new visitors.ImportVisitor(imports, finish)
                            .run(root);
                    } else {
                        return finish();
                    }
                },

                //
                // Here in, the parsing rules/functions
                //
                // The basic structure of the syntax tree generated is as follows:
                //
                //   Ruleset ->  Declaration -> Value -> Expression -> Entity
                //
                // Here's some Less code:
                //
                //    .class {
                //      color: #fff;
                //      border: 1px solid #000;
                //      width: @w + 4px;
                //      > .child {...}
                //    }
                //
                // And here's what the parse tree might look like:
                //
                //     Ruleset (Selector '.class', [
                //         Declaration ("color",  Value ([Expression [Color #fff]]))
                //         Declaration ("border", Value ([Expression [Dimension 1px][Keyword "solid"][Color #000]]))
                //         Declaration ("width",  Value ([Expression [Operation " + " [Variable "@w"][Dimension 4px]]]))
                //         Ruleset (Selector [Element '>', '.child'], [...])
                //     ])
                //
                //  In general, most rules will try to parse a token with the `$re()` function, and if the return
                //  value is truly, will return a new node, of the relevant type. Sometimes, we need to check
                //  first, before parsing, that's when we use `peek()`.
                //
                parsers: parsers = {
                    //
                    // The `primary` rule is the *entry* and *exit* point of the parser.
                    // The rules here can appear at any level of the parse tree.
                    //
                    // The recursive nature of the grammar is an interplay between the `block`
                    // rule, which represents `{ ... }`, the `ruleset` rule, and this `primary` rule,
                    // as represented by this simplified grammar:
                    //
                    //     primary  →  (ruleset | declaration)+
                    //     ruleset  →  selector+ block
                    //     block    →  '{' primary '}'
                    //
                    // Only at one point is the primary rule not called from the
                    // block rule: at the root level.
                    //
                    primary: function () {
                        var mixin = this.mixin, root = [], node;

                        while (true) {
                            while (true) {
                                node = this.comment();
                                if (!node) { break; }
                                root.push(node);
                            }
                            // always process comments before deciding if finished
                            if (parserInput.finished) {
                                break;
                            }
                            if (parserInput.peek('}')) {
                                break;
                            }

                            node = this.extendRule();
                            if (node) {
                                root = root.concat(node);
                                continue;
                            }

                            node = mixin.definition() || this.declaration() || this.ruleset() ||
                                mixin.call(false, false) || this.variableCall() || this.entities.call() || this.atrule();
                            if (node) {
                                root.push(node);
                            } else {
                                var foundSemiColon = false;
                                while (parserInput.$char(';')) {
                                    foundSemiColon = true;
                                }
                                if (!foundSemiColon) {
                                    break;
                                }
                            }
                        }

                        return root;
                    },

                    // comments are collected by the main parsing mechanism and then assigned to nodes
                    // where the current structure allows it
                    comment: function () {
                        if (parserInput.commentStore.length) {
                            var comment = parserInput.commentStore.shift();
                            return new(tree.Comment)(comment.text, comment.isLineComment, comment.index, fileInfo);
                        }
                    },

                    //
                    // Entities are tokens which can be found inside an Expression
                    //
                    entities: {
                        mixinLookup: function() {
                            return parsers.mixin.call(true, true);
                        },
                        //
                        // A string, which supports escaping " and '
                        //
                        //     "milky way" 'he\'s the one!'
                        //
                        quoted: function (forceEscaped) {
                            var str, index = parserInput.i, isEscaped = false;

                            parserInput.save();
                            if (parserInput.$char('~')) {
                                isEscaped = true;
                            } else if (forceEscaped) {
                                parserInput.restore();
                                return;
                            }

                            str = parserInput.$quoted();
                            if (!str) {
                                parserInput.restore();
                                return;
                            }
                            parserInput.forget();

                            return new(tree.Quoted)(str.charAt(0), str.substr(1, str.length - 2), isEscaped, index, fileInfo);
                        },

                        //
                        // A catch-all word, such as:
                        //
                        //     black border-collapse
                        //
                        keyword: function () {
                            var k = parserInput.$char('%') || parserInput.$re(/^\[?(?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+\]?/);
                            if (k) {
                                return tree.Color.fromKeyword(k) || new(tree.Keyword)(k);
                            }
                        },

                        //
                        // A function call
                        //
                        //     rgb(255, 0, 255)
                        //
                        // The arguments are parsed with the `entities.arguments` parser.
                        //
                        call: function () {
                            var name, args, func, index = parserInput.i;

                            // http://jsperf.com/case-insensitive-regex-vs-strtolower-then-regex/18
                            if (parserInput.peek(/^url\(/i)) {
                                return;
                            }

                            parserInput.save();

                            name = parserInput.$re(/^([\w-]+|%|progid:[\w\.]+)\(/);
                            if (!name) {
                                parserInput.forget();
                                return;
                            }

                            name = name[1];
                            func = this.customFuncCall(name);
                            if (func) {
                                args = func.parse();
                                if (args && func.stop) {
                                    parserInput.forget();
                                    return args;
                                }
                            }

                            args = this.arguments(args);

                            if (!parserInput.$char(')')) {
                                parserInput.restore('Could not parse call arguments or missing \')\'');
                                return;
                            }

                            parserInput.forget();

                            return new(tree.Call)(name, args, index, fileInfo);
                        },

                        //
                        // Parsing rules for functions with non-standard args, e.g.:
                        //
                        //     boolean(not(2 > 1))
                        //
                        //     This is a quick prototype, to be modified/improved when
                        //     more custom-parsed funcs come (e.g. `selector(...)`)
                        //

                        customFuncCall: function (name) {
                            /* Ideally the table is to be moved out of here for faster perf.,
                       but it's quite tricky since it relies on all these `parsers`
                       and `expect` available only here */
                            return {
                                alpha:   f(parsers.ieAlpha, true),
                                boolean: f(condition),
                                'if':    f(condition)
                            }[name.toLowerCase()];

                            function f(parse, stop) {
                                return {
                                    parse: parse, // parsing function
                                    stop:  stop   // when true - stop after parse() and return its result,
                                                  // otherwise continue for plain args
                                };
                            }

                            function condition() {
                                return [expect(parsers.condition, 'expected condition')];
                            }
                        },

                        arguments: function (prevArgs) {
                            var argsComma = prevArgs || [],
                                argsSemiColon = [],
                                isSemiColonSeparated, value;

                            parserInput.save();

                            while (true) {
                                if (prevArgs) {
                                    prevArgs = false;
                                } else {
                                    value = parsers.detachedRuleset() || this.assignment() || parsers.expression();
                                    if (!value) {
                                        break;
                                    }

                                    if (value.value && value.value.length == 1) {
                                        value = value.value[0];
                                    }

                                    argsComma.push(value);
                                }

                                if (parserInput.$char(',')) {
                                    continue;
                                }

                                if (parserInput.$char(';') || isSemiColonSeparated) {
                                    isSemiColonSeparated = true;
                                    value = (argsComma.length < 1) ? argsComma[0]
                                        : new tree.Value(argsComma);
                                    argsSemiColon.push(value);
                                    argsComma = [];
                                }
                            }

                            parserInput.forget();
                            return isSemiColonSeparated ? argsSemiColon : argsComma;
                        },
                        literal: function () {
                            return this.dimension() ||
                                this.color() ||
                                this.quoted() ||
                                this.unicodeDescriptor();
                        },

                        // Assignments are argument entities for calls.
                        // They are present in ie filter properties as shown below.
                        //
                        //     filter: progid:DXImageTransform.Microsoft.Alpha( *opacity=50* )
                        //

                        assignment: function () {
                            var key, value;
                            parserInput.save();
                            key = parserInput.$re(/^\w+(?=\s?=)/i);
                            if (!key) {
                                parserInput.restore();
                                return;
                            }
                            if (!parserInput.$char('=')) {
                                parserInput.restore();
                                return;
                            }
                            value = parsers.entity();
                            if (value) {
                                parserInput.forget();
                                return new(tree.Assignment)(key, value);
                            } else {
                                parserInput.restore();
                            }
                        },

                        //
                        // Parse url() tokens
                        //
                        // We use a specific rule for urls, because they don't really behave like
                        // standard function calls. The difference is that the argument doesn't have
                        // to be enclosed within a string, so it can't be parsed as an Expression.
                        //
                        url: function () {
                            var value, index = parserInput.i;

                            parserInput.autoCommentAbsorb = false;

                            if (!parserInput.$str('url(')) {
                                parserInput.autoCommentAbsorb = true;
                                return;
                            }

                            value = this.quoted() || this.variable() || this.property() ||
                                parserInput.$re(/^(?:(?:\\[\(\)'"])|[^\(\)'"])+/) || '';

                            parserInput.autoCommentAbsorb = true;

                            expectChar(')');

                            return new(tree.URL)((value.value != null ||
                                value instanceof tree.Variable ||
                                value instanceof tree.Property) ?
                                value : new(tree.Anonymous)(value, index), index, fileInfo);
                        },

                        //
                        // A Variable entity, such as `@fink`, in
                        //
                        //     width: @fink + 2px
                        //
                        // We use a different parser for variable definitions,
                        // see `parsers.variable`.
                        //
                        variable: function () {
                            var ch, name, index = parserInput.i;

                            parserInput.save();
                            if (parserInput.currentChar() === '@' && (name = parserInput.$re(/^@@?[\w-]+/))) {
                                ch = parserInput.currentChar();
                                if (ch === '(' || ch === '[' && !parserInput.prevChar().match(/^\s/)) {
                                    // this may be a VariableCall lookup
                                    var result = parsers.variableCall(name);
                                    if (result) {
                                        parserInput.forget();
                                        return result;
                                    }
                                }
                                parserInput.forget();
                                return new(tree.Variable)(name, index, fileInfo);
                            }
                            parserInput.restore();
                        },

                        // A variable entity using the protective {} e.g. @{var}
                        variableCurly: function () {
                            var curly, index = parserInput.i;

                            if (parserInput.currentChar() === '@' && (curly = parserInput.$re(/^@\{([\w-]+)\}/))) {
                                return new(tree.Variable)('@' + curly[1], index, fileInfo);
                            }
                        },
                        //
                        // A Property accessor, such as `$color`, in
                        //
                        //     background-color: $color
                        //
                        property: function () {
                            var name, index = parserInput.i;

                            if (parserInput.currentChar() === '$' && (name = parserInput.$re(/^\$[\w-]+/))) {
                                return new(tree.Property)(name, index, fileInfo);
                            }
                        },

                        // A property entity useing the protective {} e.g. ${prop}
                        propertyCurly: function () {
                            var curly, index = parserInput.i;

                            if (parserInput.currentChar() === '$' && (curly = parserInput.$re(/^\$\{([\w-]+)\}/))) {
                                return new(tree.Property)('$' + curly[1], index, fileInfo);
                            }
                        },
                        //
                        // A Hexadecimal color
                        //
                        //     #4F3C2F
                        //
                        // `rgb` and `hsl` colors are parsed through the `entities.call` parser.
                        //
                        color: function () {
                            var rgb;

                            if (parserInput.currentChar() === '#' && (rgb = parserInput.$re(/^#([A-Fa-f0-9]{8}|[A-Fa-f0-9]{6}|[A-Fa-f0-9]{3,4})/))) {
                                return new(tree.Color)(rgb[1], undefined, rgb[0]);
                            }
                        },

                        colorKeyword: function () {
                            parserInput.save();
                            var autoCommentAbsorb = parserInput.autoCommentAbsorb;
                            parserInput.autoCommentAbsorb = false;
                            var k = parserInput.$re(/^[_A-Za-z-][_A-Za-z0-9-]+/);
                            parserInput.autoCommentAbsorb = autoCommentAbsorb;
                            if (!k) {
                                parserInput.forget();
                                return;
                            }
                            parserInput.restore();
                            var color = tree.Color.fromKeyword(k);
                            if (color) {
                                parserInput.$str(k);
                                return color;
                            }
                        },

                        //
                        // A Dimension, that is, a number and a unit
                        //
                        //     0.5em 95%
                        //
                        dimension: function () {
                            if (parserInput.peekNotNumeric()) {
                                return;
                            }

                            var value = parserInput.$re(/^([+-]?\d*\.?\d+)(%|[a-z_]+)?/i);
                            if (value) {
                                return new(tree.Dimension)(value[1], value[2]);
                            }
                        },

                        //
                        // A unicode descriptor, as is used in unicode-range
                        //
                        // U+0??  or U+00A1-00A9
                        //
                        unicodeDescriptor: function () {
                            var ud;

                            ud = parserInput.$re(/^U\+[0-9a-fA-F?]+(\-[0-9a-fA-F?]+)?/);
                            if (ud) {
                                return new(tree.UnicodeDescriptor)(ud[0]);
                            }
                        },

                        //
                        // JavaScript code to be evaluated
                        //
                        //     `window.location.href`
                        //
                        javascript: function () {
                            var js, index = parserInput.i;

                            parserInput.save();

                            var escape = parserInput.$char('~');
                            var jsQuote = parserInput.$char('`');

                            if (!jsQuote) {
                                parserInput.restore();
                                return;
                            }

                            js = parserInput.$re(/^[^`]*`/);
                            if (js) {
                                parserInput.forget();
                                return new(tree.JavaScript)(js.substr(0, js.length - 1), Boolean(escape), index, fileInfo);
                            }
                            parserInput.restore('invalid javascript definition');
                        }
                    },

                    //
                    // The variable part of a variable definition. Used in the `rule` parser
                    //
                    //     @fink:
                    //
                    variable: function () {
                        var name;

                        if (parserInput.currentChar() === '@' && (name = parserInput.$re(/^(@[\w-]+)\s*:/))) { return name[1]; }
                    },

                    //
                    // Call a variable value to retrieve a detached ruleset
                    // or a value from a detached ruleset's rules.
                    //
                    //     @fink();
                    //     @fink;
                    //     color: @fink[@color];
                    //
                    variableCall: function (parsedName) {
                        var lookups, important, i = parserInput.i,
                            inValue = !!parsedName, name = parsedName;

                        parserInput.save();

                        if (name || (parserInput.currentChar() === '@'
                            && (name = parserInput.$re(/^(@[\w-]+)(\(\s*\))?/)))) {

                            lookups = this.mixin.ruleLookups();

                            if (!lookups && ((inValue && parserInput.$str('()') !== '()') || (name[2] !== '()'))) {
                                parserInput.restore('Missing \'[...]\' lookup in variable call');
                                return;
                            }

                            if (!inValue) {
                                name = name[1];
                            }

                            if (lookups && parsers.important()) {
                                important = true;
                            }

                            var call = new tree.VariableCall(name, i, fileInfo);
                            if (!inValue && parsers.end()) {
                                parserInput.forget();
                                return call;
                            }
                            else {
                                parserInput.forget();
                                return new tree.NamespaceValue(call, lookups, important, i, fileInfo);
                            }
                        }

                        parserInput.restore();
                    },

                    //
                    // extend syntax - used to extend selectors
                    //
                    extend: function(isRule) {
                        var elements, e, index = parserInput.i, option, extendList, extend;

                        if (!parserInput.$str(isRule ? '&:extend(' : ':extend(')) {
                            return;
                        }

                        do {
                            option = null;
                            elements = null;
                            while (!(option = parserInput.$re(/^(all)(?=\s*(\)|,))/))) {
                                e = this.element();
                                if (!e) {
                                    break;
                                }
                                if (elements) {
                                    elements.push(e);
                                } else {
                                    elements = [ e ];
                                }
                            }

                            option = option && option[1];
                            if (!elements) {
                                error('Missing target selector for :extend().');
                            }
                            extend = new(tree.Extend)(new(tree.Selector)(elements), option, index, fileInfo);
                            if (extendList) {
                                extendList.push(extend);
                            } else {
                                extendList = [ extend ];
                            }
                        } while (parserInput.$char(','));

                        expect(/^\)/);

                        if (isRule) {
                            expect(/^;/);
                        }

                        return extendList;
                    },

                    //
                    // extendRule - used in a rule to extend all the parent selectors
                    //
                    extendRule: function() {
                        return this.extend(true);
                    },

                    //
                    // Mixins
                    //
                    mixin: {
                        //
                        // A Mixin call, with an optional argument list
                        //
                        //     #mixins > .square(#fff);
                        //     #mixins.square(#fff);
                        //     .rounded(4px, black);
                        //     .button;
                        //
                        // We can lookup / return a value using the lookup syntax:
                        //
                        //     color: #mixin.square(#fff)[@color];
                        //
                        // The `while` loop is there because mixins can be
                        // namespaced, but we only support the child and descendant
                        // selector for now.
                        //
                        call: function (inValue, getLookup) {
                            var s = parserInput.currentChar(), important = false, lookups,
                                index = parserInput.i, elements, args, hasParens;

                            if (s !== '.' && s !== '#') { return; }

                            parserInput.save(); // stop us absorbing part of an invalid selector

                            elements = this.elements();

                            if (elements) {
                                if (parserInput.$char('(')) {
                                    args = this.args(true).args;
                                    expectChar(')');
                                    hasParens = true;
                                }

                                if (getLookup !== false) {
                                    lookups = this.ruleLookups();
                                }
                                if (getLookup === true && !lookups) {
                                    parserInput.restore();
                                    return;
                                }

                                if (inValue && !lookups && !hasParens) {
                                    // This isn't a valid in-value mixin call
                                    parserInput.restore();
                                    return;
                                }

                                if (!inValue && parsers.important()) {
                                    important = true;
                                }

                                if (inValue || parsers.end()) {
                                    parserInput.forget();
                                    var mixin = new(tree.mixin.Call)(elements, args, index, fileInfo, !lookups && important);
                                    if (lookups) {
                                        return new tree.NamespaceValue(mixin, lookups, important);
                                    }
                                    else {
                                        return mixin;
                                    }
                                }
                            }

                            parserInput.restore();
                        },
                        /**
                         * Matching elements for mixins
                         * (Start with . or # and can have > )
                         */
                        elements: function() {
                            var elements, e, c, elem, elemIndex,
                                re = /^[#.](?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/;
                            while (true) {
                                elemIndex = parserInput.i;
                                e = parserInput.$re(re);

                                if (!e) {
                                    break;
                                }
                                elem = new(tree.Element)(c, e, false, elemIndex, fileInfo);
                                if (elements) {
                                    elements.push(elem);
                                } else {
                                    elements = [ elem ];
                                }
                                c = parserInput.$char('>');
                            }
                            return elements;
                        },
                        args: function (isCall) {
                            var entities = parsers.entities,
                                returner = { args:null, variadic: false },
                                expressions = [], argsSemiColon = [], argsComma = [],
                                isSemiColonSeparated, expressionContainsNamed, name, nameLoop,
                                value, arg, expand, hasSep = true;

                            parserInput.save();

                            while (true) {
                                if (isCall) {
                                    arg = parsers.detachedRuleset() || parsers.expression();
                                } else {
                                    parserInput.commentStore.length = 0;
                                    if (parserInput.$str('...')) {
                                        returner.variadic = true;
                                        if (parserInput.$char(';') && !isSemiColonSeparated) {
                                            isSemiColonSeparated = true;
                                        }
                                        (isSemiColonSeparated ? argsSemiColon : argsComma)
                                            .push({ variadic: true });
                                        break;
                                    }
                                    arg = entities.variable() || entities.property() || entities.literal() || entities.keyword() || this.call(true);
                                }

                                if (!arg || !hasSep) {
                                    break;
                                }

                                nameLoop = null;
                                if (arg.throwAwayComments) {
                                    arg.throwAwayComments();
                                }
                                value = arg;
                                var val = null;

                                if (isCall) {
                                    // Variable
                                    if (arg.value && arg.value.length == 1) {
                                        val = arg.value[0];
                                    }
                                } else {
                                    val = arg;
                                }

                                if (val && (val instanceof tree.Variable || val instanceof tree.Property)) {
                                    if (parserInput.$char(':')) {
                                        if (expressions.length > 0) {
                                            if (isSemiColonSeparated) {
                                                error('Cannot mix ; and , as delimiter types');
                                            }
                                            expressionContainsNamed = true;
                                        }

                                        value = parsers.detachedRuleset() || parsers.expression();

                                        if (!value) {
                                            if (isCall) {
                                                error('could not understand value for named argument');
                                            } else {
                                                parserInput.restore();
                                                returner.args = [];
                                                return returner;
                                            }
                                        }
                                        nameLoop = (name = val.name);
                                    } else if (parserInput.$str('...')) {
                                        if (!isCall) {
                                            returner.variadic = true;
                                            if (parserInput.$char(';') && !isSemiColonSeparated) {
                                                isSemiColonSeparated = true;
                                            }
                                            (isSemiColonSeparated ? argsSemiColon : argsComma)
                                                .push({ name: arg.name, variadic: true });
                                            break;
                                        } else {
                                            expand = true;
                                        }
                                    } else if (!isCall) {
                                        name = nameLoop = val.name;
                                        value = null;
                                    }
                                }

                                if (value) {
                                    expressions.push(value);
                                }

                                argsComma.push({ name:nameLoop, value:value, expand:expand });

                                if (parserInput.$char(',')) {
                                    hasSep = true;
                                    continue;
                                }
                                hasSep = parserInput.$char(';') === ';';

                                if (hasSep || isSemiColonSeparated) {

                                    if (expressionContainsNamed) {
                                        error('Cannot mix ; and , as delimiter types');
                                    }

                                    isSemiColonSeparated = true;

                                    if (expressions.length > 1) {
                                        value = new(tree.Value)(expressions);
                                    }
                                    argsSemiColon.push({ name:name, value:value, expand:expand });

                                    name = null;
                                    expressions = [];
                                    expressionContainsNamed = false;
                                }
                            }

                            parserInput.forget();
                            returner.args = isSemiColonSeparated ? argsSemiColon : argsComma;
                            return returner;
                        },
                        //
                        // A Mixin definition, with a list of parameters
                        //
                        //     .rounded (@radius: 2px, @color) {
                        //        ...
                        //     }
                        //
                        // Until we have a finer grained state-machine, we have to
                        // do a look-ahead, to make sure we don't have a mixin call.
                        // See the `rule` function for more information.
                        //
                        // We start by matching `.rounded (`, and then proceed on to
                        // the argument list, which has optional default values.
                        // We store the parameters in `params`, with a `value` key,
                        // if there is a value, such as in the case of `@radius`.
                        //
                        // Once we've got our params list, and a closing `)`, we parse
                        // the `{...}` block.
                        //
                        definition: function () {
                            var name, params = [], match, ruleset, cond, variadic = false;
                            if ((parserInput.currentChar() !== '.' && parserInput.currentChar() !== '#') ||
                                parserInput.peek(/^[^{]*\}/)) {
                                return;
                            }

                            parserInput.save();

                            match = parserInput.$re(/^([#.](?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+)\s*\(/);
                            if (match) {
                                name = match[1];

                                var argInfo = this.args(false);
                                params = argInfo.args;
                                variadic = argInfo.variadic;

                                // .mixincall("@{a}");
                                // looks a bit like a mixin definition..
                                // also
                                // .mixincall(@a: {rule: set;});
                                // so we have to be nice and restore
                                if (!parserInput.$char(')')) {
                                    parserInput.restore('Missing closing \')\'');
                                    return;
                                }

                                parserInput.commentStore.length = 0;

                                if (parserInput.$str('when')) { // Guard
                                    cond = expect(parsers.conditions, 'expected condition');
                                }

                                ruleset = parsers.block();

                                if (ruleset) {
                                    parserInput.forget();
                                    return new(tree.mixin.Definition)(name, params, ruleset, cond, variadic);
                                } else {
                                    parserInput.restore();
                                }
                            } else {
                                parserInput.forget();
                            }
                        },

                        ruleLookups: function() {
                            var rule, args, lookups = [];

                            if (parserInput.currentChar() !== '[') {
                                return;
                            }

                            while (true) {
                                parserInput.save();
                                args = null;
                                rule = this.lookupValue();
                                if (!rule && rule !== '') {
                                    parserInput.restore();
                                    break;
                                }
                                lookups.push(rule);
                                parserInput.forget();
                            }
                            if (lookups.length > 0) {
                                return lookups;
                            }
                        },

                        lookupValue: function() {
                            parserInput.save();

                            if (!parserInput.$char('[')) {
                                parserInput.restore();
                                return;
                            }

                            var name = parserInput.$re(/^(?:[@$]{0,2})[_a-zA-Z0-9-]*/);

                            if (!parserInput.$char(']')) {
                                parserInput.restore();
                                return;
                            }

                            if (name || name === '') {
                                parserInput.forget();
                                return name;
                            }

                            parserInput.restore();
                        }
                    },
                    //
                    // Entities are the smallest recognized token,
                    // and can be found inside a rule's value.
                    //
                    entity: function () {
                        var entities = this.entities;

                        return this.comment() || entities.literal() || entities.variable() || entities.url() ||
                            entities.property() || entities.call() || entities.keyword() || this.mixin.call(true) ||
                            entities.javascript();
                    },

                    //
                    // A Declaration terminator. Note that we use `peek()` to check for '}',
                    // because the `block` rule will be expecting it, but we still need to make sure
                    // it's there, if ';' was omitted.
                    //
                    end: function () {
                        return parserInput.$char(';') || parserInput.peek('}');
                    },

                    //
                    // IE's alpha function
                    //
                    //     alpha(opacity=88)
                    //
                    ieAlpha: function () {
                        var value;

                        // http://jsperf.com/case-insensitive-regex-vs-strtolower-then-regex/18
                        if (!parserInput.$re(/^opacity=/i)) { return; }
                        value = parserInput.$re(/^\d+/);
                        if (!value) {
                            value = expect(parsers.entities.variable, 'Could not parse alpha');
                            value = '@{' + value.name.slice(1) + '}';
                        }
                        expectChar(')');
                        return new tree.Quoted('', 'alpha(opacity=' + value + ')');
                    },

                    //
                    // A Selector Element
                    //
                    //     div
                    //     + h1
                    //     #socks
                    //     input[type="text"]
                    //
                    // Elements are the building blocks for Selectors,
                    // they are made out of a `Combinator` (see combinator rule),
                    // and an element name, such as a tag a class, or `*`.
                    //
                    element: function () {
                        var e, c, v, index = parserInput.i;

                        c = this.combinator();

                        e = parserInput.$re(/^(?:\d+\.\d+|\d+)%/) ||
                            parserInput.$re(/^(?:[.#]?|:*)(?:[\w-]|[^\x00-\x9f]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/) ||
                            parserInput.$char('*') || parserInput.$char('&') || this.attribute() ||
                            parserInput.$re(/^\([^&()@]+\)/) ||  parserInput.$re(/^[\.#:](?=@)/) ||
                            this.entities.variableCurly();

                        if (!e) {
                            parserInput.save();
                            if (parserInput.$char('(')) {
                                if ((v = this.selector(false)) && parserInput.$char(')')) {
                                    e = new(tree.Paren)(v);
                                    parserInput.forget();
                                } else {
                                    parserInput.restore('Missing closing \')\'');
                                }
                            } else {
                                parserInput.forget();
                            }
                        }

                        if (e) { return new(tree.Element)(c, e, e instanceof tree.Variable, index, fileInfo); }
                    },

                    //
                    // Combinators combine elements together, in a Selector.
                    //
                    // Because our parser isn't white-space sensitive, special care
                    // has to be taken, when parsing the descendant combinator, ` `,
                    // as it's an empty space. We have to check the previous character
                    // in the input, to see if it's a ` ` character. More info on how
                    // we deal with this in *combinator.js*.
                    //
                    combinator: function () {
                        var c = parserInput.currentChar();

                        if (c === '/') {
                            parserInput.save();
                            var slashedCombinator = parserInput.$re(/^\/[a-z]+\//i);
                            if (slashedCombinator) {
                                parserInput.forget();
                                return new(tree.Combinator)(slashedCombinator);
                            }
                            parserInput.restore();
                        }

                        if (c === '>' || c === '+' || c === '~' || c === '|' || c === '^') {
                            parserInput.i++;
                            if (c === '^' && parserInput.currentChar() === '^') {
                                c = '^^';
                                parserInput.i++;
                            }
                            while (parserInput.isWhitespace()) { parserInput.i++; }
                            return new(tree.Combinator)(c);
                        } else if (parserInput.isWhitespace(-1)) {
                            return new(tree.Combinator)(' ');
                        } else {
                            return new(tree.Combinator)(null);
                        }
                    },
                    //
                    // A CSS Selector
                    // with less extensions e.g. the ability to extend and guard
                    //
                    //     .class > div + h1
                    //     li a:hover
                    //
                    // Selectors are made out of one or more Elements, see above.
                    //
                    selector: function (isLess) {
                        var index = parserInput.i, elements, extendList, c, e, allExtends, when, condition;
                        isLess = isLess !== false;
                        while ((isLess && (extendList = this.extend())) || (isLess && (when = parserInput.$str('when'))) || (e = this.element())) {
                            if (when) {
                                condition = expect(this.conditions, 'expected condition');
                            } else if (condition) {
                                error('CSS guard can only be used at the end of selector');
                            } else if (extendList) {
                                if (allExtends) {
                                    allExtends = allExtends.concat(extendList);
                                } else {
                                    allExtends = extendList;
                                }
                            } else {
                                if (allExtends) { error('Extend can only be used at the end of selector'); }
                                c = parserInput.currentChar();
                                if (elements) {
                                    elements.push(e);
                                } else {
                                    elements = [ e ];
                                }
                                e = null;
                            }
                            if (c === '{' || c === '}' || c === ';' || c === ',' || c === ')') {
                                break;
                            }
                        }

                        if (elements) { return new(tree.Selector)(elements, allExtends, condition, index, fileInfo); }
                        if (allExtends) { error('Extend must be used to extend a selector, it cannot be used on its own'); }
                    },
                    selectors: function () {
                        var s, selectors;
                        while (true) {
                            s = this.selector();
                            if (!s) {
                                break;
                            }
                            if (selectors) {
                                selectors.push(s);
                            } else {
                                selectors = [ s ];
                            }
                            parserInput.commentStore.length = 0;
                            if (s.condition && selectors.length > 1) {
                                error("Guards are only currently allowed on a single selector.");
                            }
                            if (!parserInput.$char(',')) { break; }
                            if (s.condition) {
                                error("Guards are only currently allowed on a single selector.");
                            }
                            parserInput.commentStore.length = 0;
                        }
                        return selectors;
                    },
                    attribute: function () {
                        if (!parserInput.$char('[')) { return; }

                        var entities = this.entities,
                            key, val, op;

                        if (!(key = entities.variableCurly())) {
                            key = expect(/^(?:[_A-Za-z0-9-\*]*\|)?(?:[_A-Za-z0-9-]|\\.)+/);
                        }

                        op = parserInput.$re(/^[|~*$^]?=/);
                        if (op) {
                            val = entities.quoted() || parserInput.$re(/^[0-9]+%/) || parserInput.$re(/^[\w-]+/) || entities.variableCurly();
                        }

                        expectChar(']');

                        return new(tree.Attribute)(key, op, val);
                    },

                    //
                    // The `block` rule is used by `ruleset` and `mixin.definition`.
                    // It's a wrapper around the `primary` rule, with added `{}`.
                    //
                    block: function () {
                        var content;
                        if (parserInput.$char('{') && (content = this.primary()) && parserInput.$char('}')) {
                            return content;
                        }
                    },

                    blockRuleset: function() {
                        var block = this.block();

                        if (block) {
                            block = new tree.Ruleset(null, block);
                        }
                        return block;
                    },

                    detachedRuleset: function() {
                        var argInfo, params, variadic;

                        parserInput.save();
                        if (parserInput.$re(/^[.#]\(/)) {
                            /**
                             * DR args currently only implemented for each() function, and not
                             * yet settable as `@dr: #(@arg) {}`
                             * This should be done when DRs are merged with mixins.
                             * See: https://github.com/less/less-meta/issues/16
                             */
                            argInfo = this.mixin.args(false);
                            params = argInfo.args;
                            variadic = argInfo.variadic;
                            if (!parserInput.$char(')')) {
                                parserInput.restore();
                                return;
                            }
                        }
                        var blockRuleset = this.blockRuleset();
                        if (blockRuleset) {
                            parserInput.forget();
                            if (params) {
                                return new tree.mixin.Definition(null, params, blockRuleset, null, variadic);
                            }
                            return new tree.DetachedRuleset(blockRuleset);
                        }
                        parserInput.restore();
                    },

                    //
                    // div, .class, body > p {...}
                    //
                    ruleset: function () {
                        var selectors, rules, debugInfo;

                        parserInput.save();

                        if (context.dumpLineNumbers) {
                            debugInfo = getDebugInfo(parserInput.i);
                        }

                        selectors = this.selectors();

                        if (selectors && (rules = this.block())) {
                            parserInput.forget();
                            var ruleset = new(tree.Ruleset)(selectors, rules, context.strictImports);
                            if (context.dumpLineNumbers) {
                                ruleset.debugInfo = debugInfo;
                            }
                            return ruleset;
                        } else {
                            parserInput.restore();
                        }
                    },
                    declaration: function () {
                        var name, value, index = parserInput.i, hasDR,
                            c = parserInput.currentChar(), important, merge, isVariable;

                        if (c === '.' || c === '#' || c === '&' || c === ':') { return; }

                        parserInput.save();

                        name = this.variable() || this.ruleProperty();
                        if (name) {
                            isVariable = typeof name === 'string';

                            if (isVariable) {
                                value = this.detachedRuleset();
                                if (value) {
                                    hasDR = true;
                                }
                            }

                            parserInput.commentStore.length = 0;
                            if (!value) {
                                // a name returned by this.ruleProperty() is always an array of the form:
                                // [string-1, ..., string-n, ""] or [string-1, ..., string-n, "+"]
                                // where each item is a tree.Keyword or tree.Variable
                                merge = !isVariable && name.length > 1 && name.pop().value;

                                // Custom property values get permissive parsing
                                if (name[0].value && name[0].value.slice(0, 2) === '--') {
                                    value = this.permissiveValue();
                                }
                                // Try to store values as anonymous
                                // If we need the value later we'll re-parse it in ruleset.parseValue
                                else {
                                    value = this.anonymousValue();
                                }
                                if (value) {
                                    parserInput.forget();
                                    // anonymous values absorb the end ';' which is required for them to work
                                    return new (tree.Declaration)(name, value, false, merge, index, fileInfo);
                                }

                                if (!value) {
                                    value = this.value();
                                }

                                if (value) {
                                    important = this.important();
                                } else if (isVariable) {
                                    // As a last resort, try permissiveValue
                                    value = this.permissiveValue();
                                }
                            }

                            if (value && (this.end() || hasDR)) {
                                parserInput.forget();
                                return new (tree.Declaration)(name, value, important, merge, index, fileInfo);
                            }
                            else {
                                parserInput.restore();
                            }
                        } else {
                            parserInput.restore();
                        }
                    },
                    anonymousValue: function () {
                        var index = parserInput.i;
                        var match = parserInput.$re(/^([^.#@\$+\/'"*`(;{}-]*);/);
                        if (match) {
                            return new(tree.Anonymous)(match[1], index);
                        }
                    },
                    /**
                     * Used for custom properties, at-rules, and variables (as fallback)
                     * Parses almost anything inside of {} [] () "" blocks
                     * until it reaches outer-most tokens.
                     *
                     * First, it will try to parse comments and entities to reach
                     * the end. This is mostly like the Expression parser except no
                     * math is allowed.
                     */
                    permissiveValue: function (untilTokens) {
                        var i, e, done, value,
                            tok = untilTokens || ';',
                            index = parserInput.i, result = [];

                        function testCurrentChar() {
                            var char = parserInput.currentChar();
                            if (typeof tok === 'string') {
                                return char === tok;
                            } else {
                                return tok.test(char);
                            }
                        }
                        if (testCurrentChar()) {
                            return;
                        }
                        value = [];
                        do {
                            e = this.comment();
                            if (e) {
                                value.push(e);
                                continue;
                            }
                            e = this.entity();
                            if (e) {
                                value.push(e);
                            }
                        } while (e);

                        done = testCurrentChar();

                        if (value.length > 0) {
                            value = new(tree.Expression)(value);
                            if (done) {
                                return value;
                            }
                            else {
                                result.push(value);
                            }
                            // Preserve space before $parseUntil as it will not
                            if (parserInput.prevChar() === ' ') {
                                result.push(new tree.Anonymous(' ', index));
                            }
                        }
                        parserInput.save();

                        value = parserInput.$parseUntil(tok);

                        if (value) {
                            if (typeof value === 'string') {
                                error('Expected \'' + value + '\'', 'Parse');
                            }
                            if (value.length === 1 && value[0] === ' ') {
                                parserInput.forget();
                                return new tree.Anonymous('', index);
                            }
                            var item;
                            for (i = 0; i < value.length; i++) {
                                item = value[i];
                                if (Array.isArray(item)) {
                                    // Treat actual quotes as normal quoted values
                                    result.push(new tree.Quoted(item[0], item[1], true, index, fileInfo));
                                }
                                else {
                                    if (i === value.length - 1) {
                                        item = item.trim();
                                    }
                                    // Treat like quoted values, but replace vars like unquoted expressions
                                    var quote = new tree.Quoted('\'', item, true, index, fileInfo);
                                    quote.variableRegex = /@([\w-]+)/g;
                                    quote.propRegex = /\$([\w-]+)/g;
                                    result.push(quote);
                                }
                            }
                            parserInput.forget();
                            return new tree.Expression(result, true);
                        }
                        parserInput.restore();
                    },

                    //
                    // An @import atrule
                    //
                    //     @import "lib";
                    //
                    // Depending on our environment, importing is done differently:
                    // In the browser, it's an XHR request, in Node, it would be a
                    // file-system operation. The function used for importing is
                    // stored in `import`, which we pass to the Import constructor.
                    //
                    'import': function () {
                        var path, features, index = parserInput.i;

                        var dir = parserInput.$re(/^@import?\s+/);

                        if (dir) {
                            var options = (dir ? this.importOptions() : null) || {};

                            if ((path = this.entities.quoted() || this.entities.url())) {
                                features = this.mediaFeatures();

                                if (!parserInput.$char(';')) {
                                    parserInput.i = index;
                                    error('missing semi-colon or unrecognised media features on import');
                                }
                                features = features && new(tree.Value)(features);
                                return new(tree.Import)(path, features, options, index, fileInfo);
                            }
                            else {
                                parserInput.i = index;
                                error('malformed import statement');
                            }
                        }
                    },

                    importOptions: function() {
                        var o, options = {}, optionName, value;

                        // list of options, surrounded by parens
                        if (!parserInput.$char('(')) { return null; }
                        do {
                            o = this.importOption();
                            if (o) {
                                optionName = o;
                                value = true;
                                switch (optionName) {
                                    case 'css':
                                        optionName = 'less';
                                        value = false;
                                        break;
                                    case 'once':
                                        optionName = 'multiple';
                                        value = false;
                                        break;
                                }
                                options[optionName] = value;
                                if (!parserInput.$char(',')) { break; }
                            }
                        } while (o);
                        expectChar(')');
                        return options;
                    },

                    importOption: function() {
                        var opt = parserInput.$re(/^(less|css|multiple|once|inline|reference|optional)/);
                        if (opt) {
                            return opt[1];
                        }
                    },

                    mediaFeature: function () {
                        var entities = this.entities, nodes = [], e, p;
                        parserInput.save();
                        do {
                            e = entities.keyword() || entities.variable() || entities.mixinLookup();
                            if (e) {
                                nodes.push(e);
                            } else if (parserInput.$char('(')) {
                                p = this.property();
                                e = this.value();
                                if (parserInput.$char(')')) {
                                    if (p && e) {
                                        nodes.push(new(tree.Paren)(new(tree.Declaration)(p, e, null, null, parserInput.i, fileInfo, true)));
                                    } else if (e) {
                                        nodes.push(new(tree.Paren)(e));
                                    } else {
                                        error('badly formed media feature definition');
                                    }
                                } else {
                                    error('Missing closing \')\'', 'Parse');
                                }
                            }
                        } while (e);

                        parserInput.forget();
                        if (nodes.length > 0) {
                            return new(tree.Expression)(nodes);
                        }
                    },

                    mediaFeatures: function () {
                        var entities = this.entities, features = [], e;
                        do {
                            e = this.mediaFeature();
                            if (e) {
                                features.push(e);
                                if (!parserInput.$char(',')) { break; }
                            } else {
                                e = entities.variable() || entities.mixinLookup();
                                if (e) {
                                    features.push(e);
                                    if (!parserInput.$char(',')) { break; }
                                }
                            }
                        } while (e);

                        return features.length > 0 ? features : null;
                    },

                    media: function () {
                        var features, rules, media, debugInfo, index = parserInput.i;

                        if (context.dumpLineNumbers) {
                            debugInfo = getDebugInfo(index);
                        }

                        parserInput.save();

                        if (parserInput.$str('@media')) {
                            features = this.mediaFeatures();

                            rules = this.block();

                            if (!rules) {
                                error('media definitions require block statements after any features');
                            }

                            parserInput.forget();

                            media = new(tree.Media)(rules, features, index, fileInfo);
                            if (context.dumpLineNumbers) {
                                media.debugInfo = debugInfo;
                            }

                            return media;
                        }

                        parserInput.restore();
                    },

                    //

                    // A @plugin directive, used to import plugins dynamically.
                    //
                    //     @plugin (args) "lib";
                    //
                    plugin: function () {
                        var path, args, options,
                            index = parserInput.i,
                            dir   = parserInput.$re(/^@plugin?\s+/);

                        if (dir) {
                            args = this.pluginArgs();

                            if (args) {
                                options = {
                                    pluginArgs: args,
                                    isPlugin: true
                                };
                            }
                            else {
                                options = { isPlugin: true };
                            }

                            if ((path = this.entities.quoted() || this.entities.url())) {

                                if (!parserInput.$char(';')) {
                                    parserInput.i = index;
                                    error('missing semi-colon on @plugin');
                                }
                                return new(tree.Import)(path, null, options, index, fileInfo);
                            }
                            else {
                                parserInput.i = index;
                                error('malformed @plugin statement');
                            }
                        }
                    },

                    pluginArgs: function() {
                        // list of options, surrounded by parens
                        parserInput.save();
                        if (!parserInput.$char('(')) {
                            parserInput.restore();
                            return null;
                        }
                        var args = parserInput.$re(/^\s*([^\);]+)\)\s*/);
                        if (args[1]) {
                            parserInput.forget();
                            return args[1].trim();
                        }
                        else {
                            parserInput.restore();
                            return null;
                        }
                    },

                    //
                    // A CSS AtRule
                    //
                    //     @charset "utf-8";
                    //
                    atrule: function () {
                        var index = parserInput.i, name, value, rules, nonVendorSpecificName,
                            hasIdentifier, hasExpression, hasUnknown, hasBlock = true, isRooted = true;

                        if (parserInput.currentChar() !== '@') { return; }

                        value = this['import']() || this.plugin() || this.media();
                        if (value) {
                            return value;
                        }

                        parserInput.save();

                        name = parserInput.$re(/^@[a-z-]+/);

                        if (!name) { return; }

                        nonVendorSpecificName = name;
                        if (name.charAt(1) == '-' && name.indexOf('-', 2) > 0) {
                            nonVendorSpecificName = '@' + name.slice(name.indexOf('-', 2) + 1);
                        }

                        switch (nonVendorSpecificName) {
                            case '@charset':
                                hasIdentifier = true;
                                hasBlock = false;
                                break;
                            case '@namespace':
                                hasExpression = true;
                                hasBlock = false;
                                break;
                            case '@keyframes':
                            case '@counter-style':
                                hasIdentifier = true;
                                break;
                            case '@document':
                            case '@supports':
                                hasUnknown = true;
                                isRooted = false;
                                break;
                            default:
                                hasUnknown = true;
                                break;
                        }

                        parserInput.commentStore.length = 0;

                        if (hasIdentifier) {
                            value = this.entity();
                            if (!value) {
                                error('expected ' + name + ' identifier');
                            }
                        } else if (hasExpression) {
                            value = this.expression();
                            if (!value) {
                                error('expected ' + name + ' expression');
                            }
                        } else if (hasUnknown) {
                            value = this.permissiveValue(/^[{;]/);
                            hasBlock = (parserInput.currentChar() === '{');
                            if (!value) {
                                if (!hasBlock && parserInput.currentChar() !== ';') {
                                    error(name + ' rule is missing block or ending semi-colon');
                                }
                            }
                            else if (!value.value) {
                                value = null;
                            }
                        }

                        if (hasBlock) {
                            rules = this.blockRuleset();
                        }

                        if (rules || (!hasBlock && value && parserInput.$char(';'))) {
                            parserInput.forget();
                            return new (tree.AtRule)(name, value, rules, index, fileInfo,
                                context.dumpLineNumbers ? getDebugInfo(index) : null,
                                isRooted
                            );
                        }

                        parserInput.restore('at-rule options not recognised');
                    },

                    //
                    // A Value is a comma-delimited list of Expressions
                    //
                    //     font-family: Baskerville, Georgia, serif;
                    //
                    // In a Rule, a Value represents everything after the `:`,
                    // and before the `;`.
                    //
                    value: function () {
                        var e, expressions = [], index = parserInput.i;

                        do {
                            e = this.expression();
                            if (e) {
                                expressions.push(e);
                                if (!parserInput.$char(',')) { break; }
                            }
                        } while (e);

                        if (expressions.length > 0) {
                            return new(tree.Value)(expressions, index);
                        }
                    },
                    important: function () {
                        if (parserInput.currentChar() === '!') {
                            return parserInput.$re(/^! *important/);
                        }
                    },
                    sub: function () {
                        var a, e;

                        parserInput.save();
                        if (parserInput.$char('(')) {
                            a = this.addition();
                            if (a && parserInput.$char(')')) {
                                parserInput.forget();
                                e = new(tree.Expression)([a]);
                                e.parens = true;
                                return e;
                            }
                            parserInput.restore('Expected \')\'');
                            return;
                        }
                        parserInput.restore();
                    },
                    multiplication: function () {
                        var m, a, op, operation, isSpaced;
                        m = this.operand();
                        if (m) {
                            isSpaced = parserInput.isWhitespace(-1);
                            while (true) {
                                if (parserInput.peek(/^\/[*\/]/)) {
                                    break;
                                }

                                parserInput.save();

                                op = parserInput.$char('/') || parserInput.$char('*') || parserInput.$str('./');

                                if (!op) { parserInput.forget(); break; }

                                a = this.operand();

                                if (!a) { parserInput.restore(); break; }
                                parserInput.forget();

                                m.parensInOp = true;
                                a.parensInOp = true;
                                operation = new(tree.Operation)(op, [operation || m, a], isSpaced);
                                isSpaced = parserInput.isWhitespace(-1);
                            }
                            return operation || m;
                        }
                    },
                    addition: function () {
                        var m, a, op, operation, isSpaced;
                        m = this.multiplication();
                        if (m) {
                            isSpaced = parserInput.isWhitespace(-1);
                            while (true) {
                                op = parserInput.$re(/^[-+]\s+/) || (!isSpaced && (parserInput.$char('+') || parserInput.$char('-')));
                                if (!op) {
                                    break;
                                }
                                a = this.multiplication();
                                if (!a) {
                                    break;
                                }

                                m.parensInOp = true;
                                a.parensInOp = true;
                                operation = new(tree.Operation)(op, [operation || m, a], isSpaced);
                                isSpaced = parserInput.isWhitespace(-1);
                            }
                            return operation || m;
                        }
                    },
                    conditions: function () {
                        var a, b, index = parserInput.i, condition;

                        a = this.condition(true);
                        if (a) {
                            while (true) {
                                if (!parserInput.peek(/^,\s*(not\s*)?\(/) || !parserInput.$char(',')) {
                                    break;
                                }
                                b = this.condition(true);
                                if (!b) {
                                    break;
                                }
                                condition = new(tree.Condition)('or', condition || a, b, index);
                            }
                            return condition || a;
                        }
                    },
                    condition: function (needsParens) {
                        var result, logical, next;
                        function or() {
                            return parserInput.$str('or');
                        }

                        result = this.conditionAnd(needsParens);
                        if (!result) {
                            return ;
                        }
                        logical = or();
                        if (logical) {
                            next = this.condition(needsParens);
                            if (next) {
                                result = new(tree.Condition)(logical, result, next);
                            } else {
                                return ;
                            }
                        }
                        return result;
                    },
                    conditionAnd: function (needsParens) {
                        var result, logical, next, self = this;
                        function insideCondition() {
                            var cond = self.negatedCondition(needsParens) || self.parenthesisCondition(needsParens);
                            if (!cond && !needsParens) {
                                return self.atomicCondition(needsParens);
                            }
                            return cond;
                        }
                        function and() {
                            return parserInput.$str('and');
                        }

                        result = insideCondition();
                        if (!result) {
                            return ;
                        }
                        logical = and();
                        if (logical) {
                            next = this.conditionAnd(needsParens);
                            if (next) {
                                result = new(tree.Condition)(logical, result, next);
                            } else {
                                return ;
                            }
                        }
                        return result;
                    },
                    negatedCondition: function (needsParens) {
                        if (parserInput.$str('not')) {
                            var result = this.parenthesisCondition(needsParens);
                            if (result) {
                                result.negate = !result.negate;
                            }
                            return result;
                        }
                    },
                    parenthesisCondition: function (needsParens) {
                        function tryConditionFollowedByParenthesis(me) {
                            var body;
                            parserInput.save();
                            body = me.condition(needsParens);
                            if (!body) {
                                parserInput.restore();
                                return ;
                            }
                            if (!parserInput.$char(')')) {
                                parserInput.restore();
                                return ;
                            }
                            parserInput.forget();
                            return body;
                        }

                        var body;
                        parserInput.save();
                        if (!parserInput.$str('(')) {
                            parserInput.restore();
                            return ;
                        }
                        body = tryConditionFollowedByParenthesis(this);
                        if (body) {
                            parserInput.forget();
                            return body;
                        }

                        body = this.atomicCondition(needsParens);
                        if (!body) {
                            parserInput.restore();
                            return ;
                        }
                        if (!parserInput.$char(')')) {
                            parserInput.restore('expected \')\' got \'' + parserInput.currentChar() + '\'');
                            return ;
                        }
                        parserInput.forget();
                        return body;
                    },
                    atomicCondition: function (needsParens) {
                        var entities = this.entities, index = parserInput.i, a, b, c, op;

                        function cond() {
                            return this.addition() || entities.keyword() || entities.quoted() || entities.mixinLookup();
                        }
                        cond = cond.bind(this);

                        a = cond();
                        if (a) {
                            if (parserInput.$char('>')) {
                                if (parserInput.$char('=')) {
                                    op = '>=';
                                } else {
                                    op = '>';
                                }
                            } else
                            if (parserInput.$char('<')) {
                                if (parserInput.$char('=')) {
                                    op = '<=';
                                } else {
                                    op = '<';
                                }
                            } else
                            if (parserInput.$char('=')) {
                                if (parserInput.$char('>')) {
                                    op = '=>';
                                } else if (parserInput.$char('<')) {
                                    op = '=<';
                                } else {
                                    op = '=';
                                }
                            }
                            if (op) {
                                b = cond();
                                if (b) {
                                    c = new(tree.Condition)(op, a, b, index, false);
                                } else {
                                    error('expected expression');
                                }
                            } else {
                                c = new(tree.Condition)('=', a, new(tree.Keyword)('true'), index, false);
                            }
                            return c;
                        }
                    },

                    //
                    // An operand is anything that can be part of an operation,
                    // such as a Color, or a Variable
                    //
                    operand: function () {
                        var entities = this.entities, negate;

                        if (parserInput.peek(/^-[@\$\(]/)) {
                            negate = parserInput.$char('-');
                        }

                        var o = this.sub() || entities.dimension() ||
                            entities.color() || entities.variable() ||
                            entities.property() || entities.call() ||
                            entities.quoted(true) || entities.colorKeyword() ||
                            entities.mixinLookup();

                        if (negate) {
                            o.parensInOp = true;
                            o = new(tree.Negative)(o);
                        }

                        return o;
                    },

                    //
                    // Expressions either represent mathematical operations,
                    // or white-space delimited Entities.
                    //
                    //     1px solid black
                    //     @var * 2
                    //
                    expression: function () {
                        var entities = [], e, delim, index = parserInput.i;

                        do {
                            e = this.comment();
                            if (e) {
                                entities.push(e);
                                continue;
                            }
                            e = this.addition() || this.entity();
                            if (e) {
                                entities.push(e);
                                // operations do not allow keyword "/" dimension (e.g. small/20px) so we support that here
                                if (!parserInput.peek(/^\/[\/*]/)) {
                                    delim = parserInput.$char('/');
                                    if (delim) {
                                        entities.push(new(tree.Anonymous)(delim, index));
                                    }
                                }
                            }
                        } while (e);
                        if (entities.length > 0) {
                            return new(tree.Expression)(entities);
                        }
                    },
                    property: function () {
                        var name = parserInput.$re(/^(\*?-?[_a-zA-Z0-9-]+)\s*:/);
                        if (name) {
                            return name[1];
                        }
                    },
                    ruleProperty: function () {
                        var name = [], index = [], s, k;

                        parserInput.save();

                        var simpleProperty = parserInput.$re(/^([_a-zA-Z0-9-]+)\s*:/);
                        if (simpleProperty) {
                            name = [new(tree.Keyword)(simpleProperty[1])];
                            parserInput.forget();
                            return name;
                        }

                        function match(re) {
                            var i = parserInput.i,
                                chunk = parserInput.$re(re);
                            if (chunk) {
                                index.push(i);
                                return name.push(chunk[1]);
                            }
                        }

                        match(/^(\*?)/);
                        while (true) {
                            if (!match(/^((?:[\w-]+)|(?:[@\$]\{[\w-]+\}))/)) {
                                break;
                            }
                        }

                        if ((name.length > 1) && match(/^((?:\+_|\+)?)\s*:/)) {
                            parserInput.forget();

                            // at last, we have the complete match now. move forward,
                            // convert name particles to tree objects and return:
                            if (name[0] === '') {
                                name.shift();
                                index.shift();
                            }
                            for (k = 0; k < name.length; k++) {
                                s = name[k];
                                name[k] = (s.charAt(0) !== '@' && s.charAt(0) !== '$') ?
                                    new(tree.Keyword)(s) :
                                    (s.charAt(0) === '@' ?
                                        new(tree.Variable)('@' + s.slice(2, -1), index[k], fileInfo) :
                                        new(tree.Property)('$' + s.slice(2, -1), index[k], fileInfo));
                            }
                            return name;
                        }
                        parserInput.restore();
                    }
                }
            };
        };
        Parser.serializeVars = function(vars) {
            var s = '';

            for (var name in vars) {
                if (Object.hasOwnProperty.call(vars, name)) {
                    var value = vars[name];
                    s += ((name[0] === '@') ? '' : '@') + name + ': ' + value +
                        ((String(value).slice(-1) === ';') ? '' : ';');
                }
            }

            return s;
        };

        module.exports = Parser;

    },{"../functions/function-registry":27,"../less-error":38,"../tree":67,"../utils":89,"../visitors":93,"./parser-input":43}],45:[function(require,module,exports){
        /**
         * Plugin Manager
         */
        var PluginManager = function(less) {
            this.less = less;
            this.visitors = [];
            this.preProcessors = [];
            this.postProcessors = [];
            this.installedPlugins = [];
            this.fileManagers = [];
            this.iterator = -1;
            this.pluginCache = {};
            this.Loader = new less.PluginLoader(less);
        };

        var pm, PluginManagerFactory = function(less, newFactory) {
            if (newFactory || !pm) {
                pm = new PluginManager(less);
            }
            return pm;
        };

        /**
         * Adds all the plugins in the array
         * @param {Array} plugins
         */
        PluginManager.prototype.addPlugins = function(plugins) {
            if (plugins) {
                for (var i = 0; i < plugins.length; i++) {
                    this.addPlugin(plugins[i]);
                }
            }
        };
        /**
         *
         * @param plugin
         * @param {String} filename
         */
        PluginManager.prototype.addPlugin = function(plugin, filename, functionRegistry) {
            this.installedPlugins.push(plugin);
            if (filename) {
                this.pluginCache[filename] = plugin;
            }
            if (plugin.install) {
                plugin.install(this.less, this, functionRegistry || this.less.functions.functionRegistry);
            }
        };
        /**
         *
         * @param filename
         */
        PluginManager.prototype.get = function(filename) {
            return this.pluginCache[filename];
        };

        /**
         * Adds a visitor. The visitor object has options on itself to determine
         * when it should run.
         * @param visitor
         */
        PluginManager.prototype.addVisitor = function(visitor) {
            this.visitors.push(visitor);
        };
        /**
         * Adds a pre processor object
         * @param {object} preProcessor
         * @param {number} priority - guidelines 1 = before import, 1000 = import, 2000 = after import
         */
        PluginManager.prototype.addPreProcessor = function(preProcessor, priority) {
            var indexToInsertAt;
            for (indexToInsertAt = 0; indexToInsertAt < this.preProcessors.length; indexToInsertAt++) {
                if (this.preProcessors[indexToInsertAt].priority >= priority) {
                    break;
                }
            }
            this.preProcessors.splice(indexToInsertAt, 0, {preProcessor: preProcessor, priority: priority});
        };
        /**
         * Adds a post processor object
         * @param {object} postProcessor
         * @param {number} priority - guidelines 1 = before compression, 1000 = compression, 2000 = after compression
         */
        PluginManager.prototype.addPostProcessor = function(postProcessor, priority) {
            var indexToInsertAt;
            for (indexToInsertAt = 0; indexToInsertAt < this.postProcessors.length; indexToInsertAt++) {
                if (this.postProcessors[indexToInsertAt].priority >= priority) {
                    break;
                }
            }
            this.postProcessors.splice(indexToInsertAt, 0, {postProcessor: postProcessor, priority: priority});
        };
        /**
         *
         * @param manager
         */
        PluginManager.prototype.addFileManager = function(manager) {
            this.fileManagers.push(manager);
        };
        /**
         *
         * @returns {Array}
         * @private
         */
        PluginManager.prototype.getPreProcessors = function() {
            var preProcessors = [];
            for (var i = 0; i < this.preProcessors.length; i++) {
                preProcessors.push(this.preProcessors[i].preProcessor);
            }
            return preProcessors;
        };
        /**
         *
         * @returns {Array}
         * @private
         */
        PluginManager.prototype.getPostProcessors = function() {
            var postProcessors = [];
            for (var i = 0; i < this.postProcessors.length; i++) {
                postProcessors.push(this.postProcessors[i].postProcessor);
            }
            return postProcessors;
        };
        /**
         *
         * @returns {Array}
         * @private
         */
        PluginManager.prototype.getVisitors = function() {
            return this.visitors;
        };

        PluginManager.prototype.visitor = function() {
            var self = this;
            return {
                first: function() {
                    self.iterator = -1;
                    return self.visitors[self.iterator];
                },
                get: function() {
                    self.iterator += 1;
                    return self.visitors[self.iterator];
                }
            };
        };
        /**
         *
         * @returns {Array}
         * @private
         */
        PluginManager.prototype.getFileManagers = function() {
            return this.fileManagers;
        };

//
        module.exports = PluginManagerFactory;

    },{}],46:[function(require,module,exports){
        var PromiseConstructor,
            utils = require('./utils');

        module.exports = function(environment, ParseTree, ImportManager) {
            var render = function (input, options, callback) {
                if (typeof options === 'function') {
                    callback = options;
                    options = utils.copyOptions(this.options, {});
                }
                else {
                    options = utils.copyOptions(this.options, options || {});
                }

                if (!callback) {
                    if (!PromiseConstructor) {
                        PromiseConstructor = typeof Promise === 'undefined' ? require('promise') : Promise;
                    }
                    var self = this;
                    return new PromiseConstructor(function (resolve, reject) {
                        render.call(self, input, options, function(err, output) {
                            if (err) {
                                reject(err);
                            } else {
                                resolve(output);
                            }
                        });
                    });
                } else {
                    this.parse(input, options, function(err, root, imports, options) {
                        if (err) { return callback(err); }

                        var result;
                        try {
                            var parseTree = new ParseTree(root, imports);
                            result = parseTree.toCSS(options);
                        }
                        catch (err) { return callback(err); }

                        callback(null, result);
                    });
                }
            };

            return render;
        };

    },{"./utils":89,"promise":undefined}],47:[function(require,module,exports){
        module.exports = function (SourceMapOutput, environment) {

            var SourceMapBuilder = function (options) {
                this.options = options;
            };

            SourceMapBuilder.prototype.toCSS = function(rootNode, options, imports) {
                var sourceMapOutput = new SourceMapOutput(
                    {
                        contentsIgnoredCharsMap: imports.contentsIgnoredChars,
                        rootNode: rootNode,
                        contentsMap: imports.contents,
                        sourceMapFilename: this.options.sourceMapFilename,
                        sourceMapURL: this.options.sourceMapURL,
                        outputFilename: this.options.sourceMapOutputFilename,
                        sourceMapBasepath: this.options.sourceMapBasepath,
                        sourceMapRootpath: this.options.sourceMapRootpath,
                        outputSourceFiles: this.options.outputSourceFiles,
                        sourceMapGenerator: this.options.sourceMapGenerator,
                        sourceMapFileInline: this.options.sourceMapFileInline
                    });

                var css = sourceMapOutput.toCSS(options);
                this.sourceMap = sourceMapOutput.sourceMap;
                this.sourceMapURL = sourceMapOutput.sourceMapURL;
                if (this.options.sourceMapInputFilename) {
                    this.sourceMapInputFilename = sourceMapOutput.normalizeFilename(this.options.sourceMapInputFilename);
                }
                if (this.options.sourceMapBasepath !== undefined && this.sourceMapURL !== undefined) {
                    this.sourceMapURL = sourceMapOutput.removeBasepath(this.sourceMapURL);
                }
                return css + this.getCSSAppendage();
            };

            SourceMapBuilder.prototype.getCSSAppendage = function() {

                var sourceMapURL = this.sourceMapURL;
                if (this.options.sourceMapFileInline) {
                    if (this.sourceMap === undefined) {
                        return '';
                    }
                    sourceMapURL = 'data:application/json;base64,' + environment.encodeBase64(this.sourceMap);
                }

                if (sourceMapURL) {
                    return '/*# sourceMappingURL=' + sourceMapURL + ' */';
                }
                return '';
            };

            SourceMapBuilder.prototype.getExternalSourceMap = function() {
                return this.sourceMap;
            };
            SourceMapBuilder.prototype.setExternalSourceMap = function(sourceMap) {
                this.sourceMap = sourceMap;
            };

            SourceMapBuilder.prototype.isInline = function() {
                return this.options.sourceMapFileInline;
            };
            SourceMapBuilder.prototype.getSourceMapURL = function() {
                return this.sourceMapURL;
            };
            SourceMapBuilder.prototype.getOutputFilename = function() {
                return this.options.sourceMapOutputFilename;
            };
            SourceMapBuilder.prototype.getInputFilename = function() {
                return this.sourceMapInputFilename;
            };

            return SourceMapBuilder;
        };

    },{}],48:[function(require,module,exports){
        module.exports = function (environment) {

            var SourceMapOutput = function (options) {
                this._css = [];
                this._rootNode = options.rootNode;
                this._contentsMap = options.contentsMap;
                this._contentsIgnoredCharsMap = options.contentsIgnoredCharsMap;
                if (options.sourceMapFilename) {
                    this._sourceMapFilename = options.sourceMapFilename.replace(/\\/g, '/');
                }
                this._outputFilename = options.outputFilename;
                this.sourceMapURL = options.sourceMapURL;
                if (options.sourceMapBasepath) {
                    this._sourceMapBasepath = options.sourceMapBasepath.replace(/\\/g, '/');
                }
                if (options.sourceMapRootpath) {
                    this._sourceMapRootpath = options.sourceMapRootpath.replace(/\\/g, '/');
                    if (this._sourceMapRootpath.charAt(this._sourceMapRootpath.length - 1) !== '/') {
                        this._sourceMapRootpath += '/';
                    }
                } else {
                    this._sourceMapRootpath = '';
                }
                this._outputSourceFiles = options.outputSourceFiles;
                this._sourceMapGeneratorConstructor = environment.getSourceMapGenerator();

                this._lineNumber = 0;
                this._column = 0;
            };

            SourceMapOutput.prototype.removeBasepath = function(path) {
                if (this._sourceMapBasepath && path.indexOf(this._sourceMapBasepath) === 0) {
                    path = path.substring(this._sourceMapBasepath.length);
                    if (path.charAt(0) === '\\' || path.charAt(0) === '/') {
                        path = path.substring(1);
                    }
                }

                return path;
            };

            SourceMapOutput.prototype.normalizeFilename = function(filename) {
                filename = filename.replace(/\\/g, '/');
                filename = this.removeBasepath(filename);
                return (this._sourceMapRootpath || '') + filename;
            };

            SourceMapOutput.prototype.add = function(chunk, fileInfo, index, mapLines) {

                // ignore adding empty strings
                if (!chunk) {
                    return;
                }

                var lines,
                    sourceLines,
                    columns,
                    sourceColumns,
                    i;

                if (fileInfo && fileInfo.filename) {
                    var inputSource = this._contentsMap[fileInfo.filename];

                    // remove vars/banner added to the top of the file
                    if (this._contentsIgnoredCharsMap[fileInfo.filename]) {
                        // adjust the index
                        index -= this._contentsIgnoredCharsMap[fileInfo.filename];
                        if (index < 0) { index = 0; }
                        // adjust the source
                        inputSource = inputSource.slice(this._contentsIgnoredCharsMap[fileInfo.filename]);
                    }
                    inputSource = inputSource.substring(0, index);
                    sourceLines = inputSource.split('\n');
                    sourceColumns = sourceLines[sourceLines.length - 1];
                }

                lines = chunk.split('\n');
                columns = lines[lines.length - 1];

                if (fileInfo && fileInfo.filename) {
                    if (!mapLines) {
                        this._sourceMapGenerator.addMapping({ generated: { line: this._lineNumber + 1, column: this._column},
                            original: { line: sourceLines.length, column: sourceColumns.length},
                            source: this.normalizeFilename(fileInfo.filename)});
                    } else {
                        for (i = 0; i < lines.length; i++) {
                            this._sourceMapGenerator.addMapping({ generated: { line: this._lineNumber + i + 1, column: i === 0 ? this._column : 0},
                                original: { line: sourceLines.length + i, column: i === 0 ? sourceColumns.length : 0},
                                source: this.normalizeFilename(fileInfo.filename)});
                        }
                    }
                }

                if (lines.length === 1) {
                    this._column += columns.length;
                } else {
                    this._lineNumber += lines.length - 1;
                    this._column = columns.length;
                }

                this._css.push(chunk);
            };

            SourceMapOutput.prototype.isEmpty = function() {
                return this._css.length === 0;
            };

            SourceMapOutput.prototype.toCSS = function(context) {
                this._sourceMapGenerator = new this._sourceMapGeneratorConstructor({ file: this._outputFilename, sourceRoot: null });

                if (this._outputSourceFiles) {
                    for (var filename in this._contentsMap) {
                        if (this._contentsMap.hasOwnProperty(filename)) {
                            var source = this._contentsMap[filename];
                            if (this._contentsIgnoredCharsMap[filename]) {
                                source = source.slice(this._contentsIgnoredCharsMap[filename]);
                            }
                            this._sourceMapGenerator.setSourceContent(this.normalizeFilename(filename), source);
                        }
                    }
                }

                this._rootNode.genCSS(context, this);

                if (this._css.length > 0) {
                    var sourceMapURL,
                        sourceMapContent = JSON.stringify(this._sourceMapGenerator.toJSON());

                    if (this.sourceMapURL) {
                        sourceMapURL = this.sourceMapURL;
                    } else if (this._sourceMapFilename) {
                        sourceMapURL = this._sourceMapFilename;
                    }
                    this.sourceMapURL = sourceMapURL;

                    this.sourceMap = sourceMapContent;
                }

                return this._css.join('');
            };

            return SourceMapOutput;
        };

    },{}],49:[function(require,module,exports){
        var contexts = require('./contexts'),
            visitor = require('./visitors'),
            tree = require('./tree');

        module.exports = function(root, options) {
            options = options || {};
            var evaldRoot,
                variables = options.variables,
                evalEnv = new contexts.Eval(options);

            //
            // Allows setting variables with a hash, so:
            //
            //   `{ color: new tree.Color('#f01') }` will become:
            //
            //   new tree.Declaration('@color',
            //     new tree.Value([
            //       new tree.Expression([
            //         new tree.Color('#f01')
            //       ])
            //     ])
            //   )
            //
            if (typeof variables === 'object' && !Array.isArray(variables)) {
                variables = Object.keys(variables).map(function (k) {
                    var value = variables[k];

                    if (!(value instanceof tree.Value)) {
                        if (!(value instanceof tree.Expression)) {
                            value = new tree.Expression([value]);
                        }
                        value = new tree.Value([value]);
                    }
                    return new tree.Declaration('@' + k, value, false, null, 0);
                });
                evalEnv.frames = [new tree.Ruleset(null, variables)];
            }

            var visitors = [
                new visitor.JoinSelectorVisitor(),
                new visitor.MarkVisibleSelectorsVisitor(true),
                new visitor.ExtendVisitor(),
                new visitor.ToCSSVisitor({compress: Boolean(options.compress)})
            ], preEvalVisitors = [], v, visitorIterator;

            /**
             * first() / get() allows visitors to be added while visiting
             *
             * @todo Add scoping for visitors just like functions for @plugin; right now they're global
             */
            if (options.pluginManager) {
                visitorIterator = options.pluginManager.visitor();
                for (var i = 0; i < 2; i++) {
                    visitorIterator.first();
                    while ((v = visitorIterator.get())) {
                        if (v.isPreEvalVisitor) {
                            if (i === 0 || preEvalVisitors.indexOf(v) === -1) {
                                preEvalVisitors.push(v);
                                v.run(root);
                            }
                        }
                        else {
                            if (i === 0 || visitors.indexOf(v) === -1) {
                                if (v.isPreVisitor) {
                                    visitors.unshift(v);
                                }
                                else {
                                    visitors.push(v);
                                }
                            }
                        }
                    }
                }
            }

            evaldRoot = root.eval(evalEnv);

            for (var i = 0; i < visitors.length; i++) {
                visitors[i].run(evaldRoot);
            }

            // Run any remaining visitors added after eval pass
            if (options.pluginManager) {
                visitorIterator.first();
                while ((v = visitorIterator.get())) {
                    if (visitors.indexOf(v) === -1 && preEvalVisitors.indexOf(v) === -1) {
                        v.run(evaldRoot);
                    }
                }
            }

            return evaldRoot;
        };

    },{"./contexts":13,"./tree":67,"./visitors":93}],50:[function(require,module,exports){
        var Node = require('./node');

        var Anonymous = function (value, index, currentFileInfo, mapLines, rulesetLike, visibilityInfo) {
            this.value = value;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.mapLines = mapLines;
            this.rulesetLike = (typeof rulesetLike === 'undefined') ? false : rulesetLike;
            this.allowRoot = true;
            this.copyVisibilityInfo(visibilityInfo);
        };
        Anonymous.prototype = new Node();
        Anonymous.prototype.type = 'Anonymous';
        Anonymous.prototype.eval = function () {
            return new Anonymous(this.value, this._index, this._fileInfo, this.mapLines, this.rulesetLike, this.visibilityInfo());
        };
        Anonymous.prototype.compare = function (other) {
            return other.toCSS && this.toCSS() === other.toCSS() ? 0 : undefined;
        };
        Anonymous.prototype.isRulesetLike = function() {
            return this.rulesetLike;
        };
        Anonymous.prototype.genCSS = function (context, output) {
            this.nodeVisible = Boolean(this.value);
            if (this.nodeVisible) {
                output.add(this.value, this._fileInfo, this._index, this.mapLines);
            }
        };
        module.exports = Anonymous;

    },{"./node":76}],51:[function(require,module,exports){
        var Node = require('./node');

        var Assignment = function (key, val) {
            this.key = key;
            this.value = val;
        };

        Assignment.prototype = new Node();
        Assignment.prototype.type = 'Assignment';
        Assignment.prototype.accept = function (visitor) {
            this.value = visitor.visit(this.value);
        };
        Assignment.prototype.eval = function (context) {
            if (this.value.eval) {
                return new Assignment(this.key, this.value.eval(context));
            }
            return this;
        };
        Assignment.prototype.genCSS = function (context, output) {
            output.add(this.key + '=');
            if (this.value.genCSS) {
                this.value.genCSS(context, output);
            } else {
                output.add(this.value);
            }
        };
        module.exports = Assignment;

    },{"./node":76}],52:[function(require,module,exports){
        var Node = require('./node'),
            Selector = require('./selector'),
            Ruleset = require('./ruleset'),
            Anonymous = require('./anonymous');

        var AtRule = function (name, value, rules, index, currentFileInfo, debugInfo, isRooted, visibilityInfo) {
            var i;

            this.name  = name;
            this.value = (value instanceof Node) ? value : (value ? new Anonymous(value) : value);
            if (rules) {
                if (Array.isArray(rules)) {
                    this.rules = rules;
                } else {
                    this.rules = [rules];
                    this.rules[0].selectors = (new Selector([], null, null, index, currentFileInfo)).createEmptySelectors();
                }
                for (i = 0; i < this.rules.length; i++) {
                    this.rules[i].allowImports = true;
                }
                this.setParent(this.rules, this);
            }
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.debugInfo = debugInfo;
            this.isRooted = isRooted || false;
            this.copyVisibilityInfo(visibilityInfo);
            this.allowRoot = true;
        };

        AtRule.prototype = new Node();
        AtRule.prototype.type = 'AtRule';
        AtRule.prototype.accept = function (visitor) {
            var value = this.value, rules = this.rules;
            if (rules) {
                this.rules = visitor.visitArray(rules);
            }
            if (value) {
                this.value = visitor.visit(value);
            }
        };
        AtRule.prototype.isRulesetLike = function() {
            return this.rules || !this.isCharset();
        };
        AtRule.prototype.isCharset = function() {
            return '@charset' === this.name;
        };
        AtRule.prototype.genCSS = function (context, output) {
            var value = this.value, rules = this.rules;
            output.add(this.name, this.fileInfo(), this.getIndex());
            if (value) {
                output.add(' ');
                value.genCSS(context, output);
            }
            if (rules) {
                this.outputRuleset(context, output, rules);
            } else {
                output.add(';');
            }
        };
        AtRule.prototype.eval = function (context) {
            var mediaPathBackup, mediaBlocksBackup, value = this.value, rules = this.rules;

            // media stored inside other atrule should not bubble over it
            // backpup media bubbling information
            mediaPathBackup = context.mediaPath;
            mediaBlocksBackup = context.mediaBlocks;
            // deleted media bubbling information
            context.mediaPath = [];
            context.mediaBlocks = [];

            if (value) {
                value = value.eval(context);
            }
            if (rules) {
                // assuming that there is only one rule at this point - that is how parser constructs the rule
                rules = [rules[0].eval(context)];
                rules[0].root = true;
            }
            // restore media bubbling information
            context.mediaPath = mediaPathBackup;
            context.mediaBlocks = mediaBlocksBackup;

            return new AtRule(this.name, value, rules,
                this.getIndex(), this.fileInfo(), this.debugInfo, this.isRooted, this.visibilityInfo());
        };
        AtRule.prototype.variable = function (name) {
            if (this.rules) {
                // assuming that there is only one rule at this point - that is how parser constructs the rule
                return Ruleset.prototype.variable.call(this.rules[0], name);
            }
        };
        AtRule.prototype.find = function () {
            if (this.rules) {
                // assuming that there is only one rule at this point - that is how parser constructs the rule
                return Ruleset.prototype.find.apply(this.rules[0], arguments);
            }
        };
        AtRule.prototype.rulesets = function () {
            if (this.rules) {
                // assuming that there is only one rule at this point - that is how parser constructs the rule
                return Ruleset.prototype.rulesets.apply(this.rules[0]);
            }
        };
        AtRule.prototype.outputRuleset = function (context, output, rules) {
            var ruleCnt = rules.length, i;
            context.tabLevel = (context.tabLevel | 0) + 1;

            // Compressed
            if (context.compress) {
                output.add('{');
                for (i = 0; i < ruleCnt; i++) {
                    rules[i].genCSS(context, output);
                }
                output.add('}');
                context.tabLevel--;
                return;
            }

            // Non-compressed
            var tabSetStr = '\n' + Array(context.tabLevel).join('  '), tabRuleStr = tabSetStr + '  ';
            if (!ruleCnt) {
                output.add(' {' + tabSetStr + '}');
            } else {
                output.add(' {' + tabRuleStr);
                rules[0].genCSS(context, output);
                for (i = 1; i < ruleCnt; i++) {
                    output.add(tabRuleStr);
                    rules[i].genCSS(context, output);
                }
                output.add(tabSetStr + '}');
            }

            context.tabLevel--;
        };
        module.exports = AtRule;

    },{"./anonymous":50,"./node":76,"./ruleset":81,"./selector":82}],53:[function(require,module,exports){
        var Node = require('./node');

        var Attribute = function (key, op, value) {
            this.key = key;
            this.op = op;
            this.value = value;
        };
        Attribute.prototype = new Node();
        Attribute.prototype.type = 'Attribute';
        Attribute.prototype.eval = function (context) {
            return new Attribute(this.key.eval ? this.key.eval(context) : this.key,
                this.op, (this.value && this.value.eval) ? this.value.eval(context) : this.value);
        };
        Attribute.prototype.genCSS = function (context, output) {
            output.add(this.toCSS(context));
        };
        Attribute.prototype.toCSS = function (context) {
            var value = this.key.toCSS ? this.key.toCSS(context) : this.key;

            if (this.op) {
                value += this.op;
                value += (this.value.toCSS ? this.value.toCSS(context) : this.value);
            }

            return '[' + value + ']';
        };
        module.exports = Attribute;

    },{"./node":76}],54:[function(require,module,exports){
        var Node = require('./node'),
            Anonymous = require('./anonymous'),
            FunctionCaller = require('../functions/function-caller');
//
// A function call node.
//
        var Call = function (name, args, index, currentFileInfo) {
            this.name = name;
            this.args = args;
            this.calc = name === 'calc';
            this._index = index;
            this._fileInfo = currentFileInfo;
        };
        Call.prototype = new Node();
        Call.prototype.type = 'Call';
        Call.prototype.accept = function (visitor) {
            if (this.args) {
                this.args = visitor.visitArray(this.args);
            }
        };
//
// When evaluating a function call,
// we either find the function in the functionRegistry,
// in which case we call it, passing the  evaluated arguments,
// if this returns null or we cannot find the function, we
// simply print it out as it appeared originally [2].
//
// The reason why we evaluate the arguments, is in the case where
// we try to pass a variable to a function, like: `saturate(@color)`.
// The function should receive the value, not the variable.
//
        Call.prototype.eval = function (context) {
            /**
             * Turn off math for calc(), and switch back on for evaluating nested functions
             */
            var currentMathContext = context.mathOn;
            context.mathOn = !this.calc;
            if (this.calc || context.inCalc) {
                context.enterCalc();
            }
            var args = this.args.map(function (a) { return a.eval(context); });
            if (this.calc || context.inCalc) {
                context.exitCalc();
            }
            context.mathOn = currentMathContext;

            var result, funcCaller = new FunctionCaller(this.name, context, this.getIndex(), this.fileInfo());

            if (funcCaller.isValid()) {
                try {
                    result = funcCaller.call(args);
                } catch (e) {
                    throw {
                        type: e.type || 'Runtime',
                        message: 'error evaluating function `' + this.name + '`' +
                            (e.message ? ': ' + e.message : ''),
                        index: this.getIndex(),
                        filename: this.fileInfo().filename,
                        line: e.lineNumber,
                        column: e.columnNumber
                    };
                }

                if (result !== null && result !== undefined) {
                    // Results that that are not nodes are cast as Anonymous nodes
                    // Falsy values or booleans are returned as empty nodes
                    if (!(result instanceof Node)) {
                        if (!result || result === true) {
                            result = new Anonymous(null);
                        }
                        else {
                            result = new Anonymous(result.toString());
                        }

                    }
                    result._index = this._index;
                    result._fileInfo = this._fileInfo;
                    return result;
                }

            }

            return new Call(this.name, args, this.getIndex(), this.fileInfo());
        };
        Call.prototype.genCSS = function (context, output) {
            output.add(this.name + '(', this.fileInfo(), this.getIndex());

            for (var i = 0; i < this.args.length; i++) {
                this.args[i].genCSS(context, output);
                if (i + 1 < this.args.length) {
                    output.add(', ');
                }
            }

            output.add(')');
        };
        module.exports = Call;

    },{"../functions/function-caller":26,"./anonymous":50,"./node":76}],55:[function(require,module,exports){
        var Node = require('./node'),
            colors = require('../data/colors');

//
// RGB Colors - #ff0014, #eee
//
        var Color = function (rgb, a, originalForm) {
            var self = this;
            //
            // The end goal here, is to parse the arguments
            // into an integer triplet, such as `128, 255, 0`
            //
            // This facilitates operations and conversions.
            //
            if (Array.isArray(rgb)) {
                this.rgb = rgb;
            } else if (rgb.length >= 6) {
                this.rgb = [];
                rgb.match(/.{2}/g).map(function (c, i) {
                    if (i < 3) {
                        self.rgb.push(parseInt(c, 16));
                    } else {
                        self.alpha = (parseInt(c, 16)) / 255;
                    }
                });
            } else {
                this.rgb = [];
                rgb.split('').map(function (c, i) {
                    if (i < 3) {
                        self.rgb.push(parseInt(c + c, 16));
                    } else {
                        self.alpha = (parseInt(c + c, 16)) / 255;
                    }
                });
            }
            this.alpha = this.alpha || (typeof a === 'number' ? a : 1);
            if (typeof originalForm !== 'undefined') {
                this.value = originalForm;
            }
        };

        Color.prototype = new Node();
        Color.prototype.type = 'Color';

        function clamp(v, max) {
            return Math.min(Math.max(v, 0), max);
        }

        function toHex(v) {
            return '#' + v.map(function (c) {
                c = clamp(Math.round(c), 255);
                return (c < 16 ? '0' : '') + c.toString(16);
            }).join('');
        }

        Color.prototype.luma = function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255;

            r = (r <= 0.03928) ? r / 12.92 : Math.pow(((r + 0.055) / 1.055), 2.4);
            g = (g <= 0.03928) ? g / 12.92 : Math.pow(((g + 0.055) / 1.055), 2.4);
            b = (b <= 0.03928) ? b / 12.92 : Math.pow(((b + 0.055) / 1.055), 2.4);

            return 0.2126 * r + 0.7152 * g + 0.0722 * b;
        };
        Color.prototype.genCSS = function (context, output) {
            output.add(this.toCSS(context));
        };
        Color.prototype.toCSS = function (context, doNotCompress) {
            var compress = context && context.compress && !doNotCompress, color, alpha,
                colorFunction, args = [];

            // `value` is set if this color was originally
            // converted from a named color string so we need
            // to respect this and try to output named color too.
            alpha = this.fround(context, this.alpha);

            if (this.value) {
                if (this.value.indexOf('rgb') === 0) {
                    if (alpha < 1) {
                        colorFunction = 'rgba';
                    }
                } else if (this.value.indexOf('hsl') === 0) {
                    if (alpha < 1) {
                        colorFunction = 'hsla';
                    } else {
                        colorFunction = 'hsl';
                    }
                } else {
                    return this.value;
                }
            } else {
                if (alpha < 1) {
                    colorFunction = 'rgba';
                }
            }

            switch (colorFunction) {
                case 'rgba':
                    args = this.rgb.map(function (c) {
                        return clamp(Math.round(c), 255);
                    }).concat(clamp(alpha, 1));
                    break;
                case 'hsla':
                    args.push(clamp(alpha, 1));
                case 'hsl':
                    color = this.toHSL();
                    args = [
                        this.fround(context, color.h),
                        this.fround(context, color.s * 100) + '%',
                        this.fround(context, color.l * 100) + '%'
                    ].concat(args);
            }

            if (colorFunction) {
                // Values are capped between `0` and `255`, rounded and zero-padded.
                return colorFunction + '(' + args.join(',' + (compress ? '' : ' ')) + ')';
            }

            color = this.toRGB();

            if (compress) {
                var splitcolor = color.split('');

                // Convert color to short format
                if (splitcolor[1] === splitcolor[2] && splitcolor[3] === splitcolor[4] && splitcolor[5] === splitcolor[6]) {
                    color = '#' + splitcolor[1] + splitcolor[3] + splitcolor[5];
                }
            }

            return color;
        };

//
// Operations have to be done per-channel, if not,
// channels will spill onto each other. Once we have
// our result, in the form of an integer triplet,
// we create a new Color node to hold the result.
//
        Color.prototype.operate = function (context, op, other) {
            var rgb = new Array(3);
            var alpha = this.alpha * (1 - other.alpha) + other.alpha;
            for (var c = 0; c < 3; c++) {
                rgb[c] = this._operate(context, op, this.rgb[c], other.rgb[c]);
            }
            return new Color(rgb, alpha);
        };
        Color.prototype.toRGB = function () {
            return toHex(this.rgb);
        };
        Color.prototype.toHSL = function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255,
                a = this.alpha;

            var max = Math.max(r, g, b), min = Math.min(r, g, b);
            var h, s, l = (max + min) / 2, d = max - min;

            if (max === min) {
                h = s = 0;
            } else {
                s = l > 0.5 ? d / (2 - max - min) : d / (max + min);

                switch (max) {
                    case r: h = (g - b) / d + (g < b ? 6 : 0); break;
                    case g: h = (b - r) / d + 2;               break;
                    case b: h = (r - g) / d + 4;               break;
                }
                h /= 6;
            }
            return { h: h * 360, s: s, l: l, a: a };
        };
// Adapted from http://mjijackson.com/2008/02/rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript
        Color.prototype.toHSV = function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255,
                a = this.alpha;

            var max = Math.max(r, g, b), min = Math.min(r, g, b);
            var h, s, v = max;

            var d = max - min;
            if (max === 0) {
                s = 0;
            } else {
                s = d / max;
            }

            if (max === min) {
                h = 0;
            } else {
                switch (max) {
                    case r: h = (g - b) / d + (g < b ? 6 : 0); break;
                    case g: h = (b - r) / d + 2; break;
                    case b: h = (r - g) / d + 4; break;
                }
                h /= 6;
            }
            return { h: h * 360, s: s, v: v, a: a };
        };
        Color.prototype.toARGB = function () {
            return toHex([this.alpha * 255].concat(this.rgb));
        };
        Color.prototype.compare = function (x) {
            return (x.rgb &&
                x.rgb[0] === this.rgb[0] &&
                x.rgb[1] === this.rgb[1] &&
                x.rgb[2] === this.rgb[2] &&
                x.alpha  === this.alpha) ? 0 : undefined;
        };

        Color.fromKeyword = function(keyword) {
            var c, key = keyword.toLowerCase();
            if (colors.hasOwnProperty(key)) {
                c = new Color(colors[key].slice(1));
            }
            else if (key === 'transparent') {
                c = new Color([0, 0, 0], 0);
            }

            if (c) {
                c.value = keyword;
                return c;
            }
        };
        module.exports = Color;

    },{"../data/colors":14,"./node":76}],56:[function(require,module,exports){
        var Node = require('./node');

        var Combinator = function (value) {
            if (value === ' ') {
                this.value = ' ';
                this.emptyOrWhitespace = true;
            } else {
                this.value = value ? value.trim() : '';
                this.emptyOrWhitespace = this.value === '';
            }
        };
        Combinator.prototype = new Node();
        Combinator.prototype.type = 'Combinator';
        var _noSpaceCombinators = {
            '': true,
            ' ': true,
            '|': true
        };
        Combinator.prototype.genCSS = function (context, output) {
            var spaceOrEmpty = (context.compress || _noSpaceCombinators[this.value]) ? '' : ' ';
            output.add(spaceOrEmpty + this.value + spaceOrEmpty);
        };
        module.exports = Combinator;

    },{"./node":76}],57:[function(require,module,exports){
        var Node = require('./node'),
            getDebugInfo = require('./debug-info');

        var Comment = function (value, isLineComment, index, currentFileInfo) {
            this.value = value;
            this.isLineComment = isLineComment;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.allowRoot = true;
        };
        Comment.prototype = new Node();
        Comment.prototype.type = 'Comment';
        Comment.prototype.genCSS = function (context, output) {
            if (this.debugInfo) {
                output.add(getDebugInfo(context, this), this.fileInfo(), this.getIndex());
            }
            output.add(this.value);
        };
        Comment.prototype.isSilent = function(context) {
            var isCompressed = context.compress && this.value[2] !== '!';
            return this.isLineComment || isCompressed;
        };
        module.exports = Comment;

    },{"./debug-info":59,"./node":76}],58:[function(require,module,exports){
        var Node = require('./node');

        var Condition = function (op, l, r, i, negate) {
            this.op = op.trim();
            this.lvalue = l;
            this.rvalue = r;
            this._index = i;
            this.negate = negate;
        };
        Condition.prototype = new Node();
        Condition.prototype.type = 'Condition';
        Condition.prototype.accept = function (visitor) {
            this.lvalue = visitor.visit(this.lvalue);
            this.rvalue = visitor.visit(this.rvalue);
        };
        Condition.prototype.eval = function (context) {
            var result = (function (op, a, b) {
                switch (op) {
                    case 'and': return a && b;
                    case 'or':  return a || b;
                    default:
                        switch (Node.compare(a, b)) {
                            case -1:
                                return op === '<' || op === '=<' || op === '<=';
                            case 0:
                                return op === '=' || op === '>=' || op === '=<' || op === '<=';
                            case 1:
                                return op === '>' || op === '>=';
                            default:
                                return false;
                        }
                }
            })(this.op, this.lvalue.eval(context), this.rvalue.eval(context));

            return this.negate ? !result : result;
        };
        module.exports = Condition;

    },{"./node":76}],59:[function(require,module,exports){
        var debugInfo = function(context, ctx, lineSeparator) {
            var result = '';
            if (context.dumpLineNumbers && !context.compress) {
                switch (context.dumpLineNumbers) {
                    case 'comments':
                        result = debugInfo.asComment(ctx);
                        break;
                    case 'mediaquery':
                        result = debugInfo.asMediaQuery(ctx);
                        break;
                    case 'all':
                        result = debugInfo.asComment(ctx) + (lineSeparator || '') + debugInfo.asMediaQuery(ctx);
                        break;
                }
            }
            return result;
        };

        debugInfo.asComment = function(ctx) {
            return '/* line ' + ctx.debugInfo.lineNumber + ', ' + ctx.debugInfo.fileName + ' */\n';
        };

        debugInfo.asMediaQuery = function(ctx) {
            var filenameWithProtocol = ctx.debugInfo.fileName;
            if (!/^[a-z]+:\/\//i.test(filenameWithProtocol)) {
                filenameWithProtocol = 'file://' + filenameWithProtocol;
            }
            return '@media -sass-debug-info{filename{font-family:' +
                filenameWithProtocol.replace(/([.:\/\\])/g, function (a) {
                    if (a == '\\') {
                        a = '\/';
                    }
                    return '\\' + a;
                }) +
                '}line{font-family:\\00003' + ctx.debugInfo.lineNumber + '}}\n';
        };

        module.exports = debugInfo;

    },{}],60:[function(require,module,exports){
        var Node = require('./node'),
            Value = require('./value'),
            Keyword = require('./keyword'),
            Anonymous = require('./anonymous'),
            MATH = require('../constants').Math;

        var Declaration = function (name, value, important, merge, index, currentFileInfo, inline, variable) {
            this.name = name;
            this.value = (value instanceof Node) ? value : new Value([value ? new Anonymous(value) : null]);
            this.important = important ? ' ' + important.trim() : '';
            this.merge = merge;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.inline = inline || false;
            this.variable = (variable !== undefined) ? variable
                : (name.charAt && (name.charAt(0) === '@'));
            this.allowRoot = true;
            this.setParent(this.value, this);
        };

        function evalName(context, name) {
            var value = '', i, n = name.length,
                output = {add: function (s) {value += s;}};
            for (i = 0; i < n; i++) {
                name[i].eval(context).genCSS(context, output);
            }
            return value;
        }

        Declaration.prototype = new Node();
        Declaration.prototype.type = 'Declaration';
        Declaration.prototype.genCSS = function (context, output) {
            output.add(this.name + (context.compress ? ':' : ': '), this.fileInfo(), this.getIndex());
            try {
                this.value.genCSS(context, output);
            }
            catch (e) {
                e.index = this._index;
                e.filename = this._fileInfo.filename;
                throw e;
            }
            output.add(this.important + ((this.inline || (context.lastRule && context.compress)) ? '' : ';'), this._fileInfo, this._index);
        };
        Declaration.prototype.eval = function (context) {
            var mathBypass = false, prevMath, name = this.name, evaldValue, variable = this.variable;
            if (typeof name !== 'string') {
                // expand 'primitive' name directly to get
                // things faster (~10% for benchmark.less):
                name = (name.length === 1) && (name[0] instanceof Keyword) ?
                    name[0].value : evalName(context, name);
                variable = false; // never treat expanded interpolation as new variable name
            }

            // @todo remove when parens-division is default
            if (name === 'font' && context.math === MATH.ALWAYS) {
                mathBypass = true;
                prevMath = context.math;
                context.math = MATH.PARENS_DIVISION;
            }
            try {
                context.importantScope.push({});
                evaldValue = this.value.eval(context);

                if (!this.variable && evaldValue.type === 'DetachedRuleset') {
                    throw { message: 'Rulesets cannot be evaluated on a property.',
                        index: this.getIndex(), filename: this.fileInfo().filename };
                }
                var important = this.important,
                    importantResult = context.importantScope.pop();
                if (!important && importantResult.important) {
                    important = importantResult.important;
                }

                return new Declaration(name,
                    evaldValue,
                    important,
                    this.merge,
                    this.getIndex(), this.fileInfo(), this.inline,
                    variable);
            }
            catch (e) {
                if (typeof e.index !== 'number') {
                    e.index = this.getIndex();
                    e.filename = this.fileInfo().filename;
                }
                throw e;
            }
            finally {
                if (mathBypass) {
                    context.math = prevMath;
                }
            }
        };
        Declaration.prototype.makeImportant = function () {
            return new Declaration(this.name,
                this.value,
                '!important',
                this.merge,
                this.getIndex(), this.fileInfo(), this.inline);
        };

        module.exports = Declaration;
    },{"../constants":12,"./anonymous":50,"./keyword":70,"./node":76,"./value":86}],61:[function(require,module,exports){
        var Node = require('./node'),
            contexts = require('../contexts'),
            utils = require('../utils');

        var DetachedRuleset = function (ruleset, frames) {
            this.ruleset = ruleset;
            this.frames = frames;
            this.setParent(this.ruleset, this);
        };
        DetachedRuleset.prototype = new Node();
        DetachedRuleset.prototype.type = 'DetachedRuleset';
        DetachedRuleset.prototype.evalFirst = true;
        DetachedRuleset.prototype.accept = function (visitor) {
            this.ruleset = visitor.visit(this.ruleset);
        };
        DetachedRuleset.prototype.eval = function (context) {
            var frames = this.frames || utils.copyArray(context.frames);
            return new DetachedRuleset(this.ruleset, frames);
        };
        DetachedRuleset.prototype.callEval = function (context) {
            return this.ruleset.eval(this.frames ? new contexts.Eval(context, this.frames.concat(context.frames)) : context);
        };
        module.exports = DetachedRuleset;

    },{"../contexts":13,"../utils":89,"./node":76}],62:[function(require,module,exports){
        var Node = require('./node'),
            unitConversions = require('../data/unit-conversions'),
            Unit = require('./unit'),
            Color = require('./color');

//
// A number with a unit
//
        var Dimension = function (value, unit) {
            this.value = parseFloat(value);
            if (isNaN(this.value)) {
                throw new Error('Dimension is not a number.');
            }
            this.unit = (unit && unit instanceof Unit) ? unit :
                new Unit(unit ? [unit] : undefined);
            this.setParent(this.unit, this);
        };

        Dimension.prototype = new Node();
        Dimension.prototype.type = 'Dimension';
        Dimension.prototype.accept = function (visitor) {
            this.unit = visitor.visit(this.unit);
        };
        Dimension.prototype.eval = function (context) {
            return this;
        };
        Dimension.prototype.toColor = function () {
            return new Color([this.value, this.value, this.value]);
        };
        Dimension.prototype.genCSS = function (context, output) {
            if ((context && context.strictUnits) && !this.unit.isSingular()) {
                throw new Error('Multiple units in dimension. Correct the units or use the unit function. Bad unit: ' + this.unit.toString());
            }

            var value = this.fround(context, this.value),
                strValue = String(value);

            if (value !== 0 && value < 0.000001 && value > -0.000001) {
                // would be output 1e-6 etc.
                strValue = value.toFixed(20).replace(/0+$/, '');
            }

            if (context && context.compress) {
                // Zero values doesn't need a unit
                if (value === 0 && this.unit.isLength()) {
                    output.add(strValue);
                    return;
                }

                // Float values doesn't need a leading zero
                if (value > 0 && value < 1) {
                    strValue = (strValue).substr(1);
                }
            }

            output.add(strValue);
            this.unit.genCSS(context, output);
        };

// In an operation between two Dimensions,
// we default to the first Dimension's unit,
// so `1px + 2` will yield `3px`.
        Dimension.prototype.operate = function (context, op, other) {
            /* jshint noempty:false */
            var value = this._operate(context, op, this.value, other.value),
                unit = this.unit.clone();

            if (op === '+' || op === '-') {
                if (unit.numerator.length === 0 && unit.denominator.length === 0) {
                    unit = other.unit.clone();
                    if (this.unit.backupUnit) {
                        unit.backupUnit = this.unit.backupUnit;
                    }
                } else if (other.unit.numerator.length === 0 && unit.denominator.length === 0) {
                    // do nothing
                } else {
                    other = other.convertTo(this.unit.usedUnits());

                    if (context.strictUnits && other.unit.toString() !== unit.toString()) {
                        throw new Error('Incompatible units. Change the units or use the unit function. Bad units: \'' + unit.toString() +
                            '\' and \'' + other.unit.toString() + '\'.');
                    }

                    value = this._operate(context, op, this.value, other.value);
                }
            } else if (op === '*') {
                unit.numerator = unit.numerator.concat(other.unit.numerator).sort();
                unit.denominator = unit.denominator.concat(other.unit.denominator).sort();
                unit.cancel();
            } else if (op === '/') {
                unit.numerator = unit.numerator.concat(other.unit.denominator).sort();
                unit.denominator = unit.denominator.concat(other.unit.numerator).sort();
                unit.cancel();
            }
            return new Dimension(value, unit);
        };
        Dimension.prototype.compare = function (other) {
            var a, b;

            if (!(other instanceof Dimension)) {
                return undefined;
            }

            if (this.unit.isEmpty() || other.unit.isEmpty()) {
                a = this;
                b = other;
            } else {
                a = this.unify();
                b = other.unify();
                if (a.unit.compare(b.unit) !== 0) {
                    return undefined;
                }
            }

            return Node.numericCompare(a.value, b.value);
        };
        Dimension.prototype.unify = function () {
            return this.convertTo({ length: 'px', duration: 's', angle: 'rad' });
        };
        Dimension.prototype.convertTo = function (conversions) {
            var value = this.value, unit = this.unit.clone(),
                i, groupName, group, targetUnit, derivedConversions = {}, applyUnit;

            if (typeof conversions === 'string') {
                for (i in unitConversions) {
                    if (unitConversions[i].hasOwnProperty(conversions)) {
                        derivedConversions = {};
                        derivedConversions[i] = conversions;
                    }
                }
                conversions = derivedConversions;
            }
            applyUnit = function (atomicUnit, denominator) {
                /* jshint loopfunc:true */
                if (group.hasOwnProperty(atomicUnit)) {
                    if (denominator) {
                        value = value / (group[atomicUnit] / group[targetUnit]);
                    } else {
                        value = value * (group[atomicUnit] / group[targetUnit]);
                    }

                    return targetUnit;
                }

                return atomicUnit;
            };

            for (groupName in conversions) {
                if (conversions.hasOwnProperty(groupName)) {
                    targetUnit = conversions[groupName];
                    group = unitConversions[groupName];

                    unit.map(applyUnit);
                }
            }

            unit.cancel();

            return new Dimension(value, unit);
        };
        module.exports = Dimension;

    },{"../data/unit-conversions":16,"./color":55,"./node":76,"./unit":84}],63:[function(require,module,exports){
        var Node = require('./node'),
            Paren = require('./paren'),
            Combinator = require('./combinator');

        var Element = function (combinator, value, isVariable, index, currentFileInfo, visibilityInfo) {
            this.combinator = combinator instanceof Combinator ?
                combinator : new Combinator(combinator);

            if (typeof value === 'string') {
                this.value = value.trim();
            } else if (value) {
                this.value = value;
            } else {
                this.value = '';
            }
            this.isVariable = isVariable;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.copyVisibilityInfo(visibilityInfo);
            this.setParent(this.combinator, this);
        };
        Element.prototype = new Node();
        Element.prototype.type = 'Element';
        Element.prototype.accept = function (visitor) {
            var value = this.value;
            this.combinator = visitor.visit(this.combinator);
            if (typeof value === 'object') {
                this.value = visitor.visit(value);
            }
        };
        Element.prototype.eval = function (context) {
            return new Element(this.combinator,
                this.value.eval ? this.value.eval(context) : this.value,
                this.isVariable,
                this.getIndex(),
                this.fileInfo(), this.visibilityInfo());
        };
        Element.prototype.clone = function () {
            return new Element(this.combinator,
                this.value,
                this.isVariable,
                this.getIndex(),
                this.fileInfo(), this.visibilityInfo());
        };
        Element.prototype.genCSS = function (context, output) {
            output.add(this.toCSS(context), this.fileInfo(), this.getIndex());
        };
        Element.prototype.toCSS = function (context) {
            context = context || {};
            var value = this.value, firstSelector = context.firstSelector;
            if (value instanceof Paren) {
                // selector in parens should not be affected by outer selector
                // flags (breaks only interpolated selectors - see #1973)
                context.firstSelector = true;
            }
            value = value.toCSS ? value.toCSS(context) : value;
            context.firstSelector = firstSelector;
            if (value === '' && this.combinator.value.charAt(0) === '&') {
                return '';
            } else {
                return this.combinator.toCSS(context) + value;
            }
        };
        module.exports = Element;

    },{"./combinator":56,"./node":76,"./paren":78}],64:[function(require,module,exports){
        var Node = require('./node'),
            Paren = require('./paren'),
            Comment = require('./comment'),
            Dimension = require('./dimension'),
            MATH = require('../constants').Math;

        var Expression = function (value, noSpacing) {
            this.value = value;
            this.noSpacing = noSpacing;
            if (!value) {
                throw new Error('Expression requires an array parameter');
            }
        };
        Expression.prototype = new Node();
        Expression.prototype.type = 'Expression';
        Expression.prototype.accept = function (visitor) {
            this.value = visitor.visitArray(this.value);
        };
        Expression.prototype.eval = function (context) {
            var returnValue,
                mathOn = context.isMathOn(),
                inParenthesis = this.parens &&
                    (context.math !== MATH.STRICT_LEGACY || !this.parensInOp),
                doubleParen = false;
            if (inParenthesis) {
                context.inParenthesis();
            }
            if (this.value.length > 1) {
                returnValue = new Expression(this.value.map(function (e) {
                    if (!e.eval) {
                        return e;
                    }
                    return e.eval(context);
                }), this.noSpacing);
            } else if (this.value.length === 1) {
                if (this.value[0].parens && !this.value[0].parensInOp && !context.inCalc) {
                    doubleParen = true;
                }
                returnValue = this.value[0].eval(context);
            } else {
                returnValue = this;
            }
            if (inParenthesis) {
                context.outOfParenthesis();
            }
            if (this.parens && this.parensInOp && !mathOn && !doubleParen
                && (!(returnValue instanceof Dimension))) {
                returnValue = new Paren(returnValue);
            }
            return returnValue;
        };
        Expression.prototype.genCSS = function (context, output) {
            for (var i = 0; i < this.value.length; i++) {
                this.value[i].genCSS(context, output);
                if (!this.noSpacing && i + 1 < this.value.length) {
                    output.add(' ');
                }
            }
        };
        Expression.prototype.throwAwayComments = function () {
            this.value = this.value.filter(function(v) {
                return !(v instanceof Comment);
            });
        };
        module.exports = Expression;

    },{"../constants":12,"./comment":57,"./dimension":62,"./node":76,"./paren":78}],65:[function(require,module,exports){
        var Node = require('./node'),
            Selector = require('./selector');

        var Extend = function Extend(selector, option, index, currentFileInfo, visibilityInfo) {
            this.selector = selector;
            this.option = option;
            this.object_id = Extend.next_id++;
            this.parent_ids = [this.object_id];
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.copyVisibilityInfo(visibilityInfo);
            this.allowRoot = true;

            switch (option) {
                case 'all':
                    this.allowBefore = true;
                    this.allowAfter = true;
                    break;
                default:
                    this.allowBefore = false;
                    this.allowAfter = false;
                    break;
            }
            this.setParent(this.selector, this);
        };
        Extend.next_id = 0;

        Extend.prototype = new Node();
        Extend.prototype.type = 'Extend';
        Extend.prototype.accept = function (visitor) {
            this.selector = visitor.visit(this.selector);
        };
        Extend.prototype.eval = function (context) {
            return new Extend(this.selector.eval(context), this.option, this.getIndex(), this.fileInfo(), this.visibilityInfo());
        };
        Extend.prototype.clone = function (context) {
            return new Extend(this.selector, this.option, this.getIndex(), this.fileInfo(), this.visibilityInfo());
        };
// it concatenates (joins) all selectors in selector array
        Extend.prototype.findSelfSelectors = function (selectors) {
            var selfElements = [],
                i,
                selectorElements;

            for (i = 0; i < selectors.length; i++) {
                selectorElements = selectors[i].elements;
                // duplicate the logic in genCSS function inside the selector node.
                // future TODO - move both logics into the selector joiner visitor
                if (i > 0 && selectorElements.length && selectorElements[0].combinator.value === '') {
                    selectorElements[0].combinator.value = ' ';
                }
                selfElements = selfElements.concat(selectors[i].elements);
            }

            this.selfSelectors = [new Selector(selfElements)];
            this.selfSelectors[0].copyVisibilityInfo(this.visibilityInfo());
        };
        module.exports = Extend;

    },{"./node":76,"./selector":82}],66:[function(require,module,exports){
        var Node = require('./node'),
            Media = require('./media'),
            URL = require('./url'),
            Quoted = require('./quoted'),
            Ruleset = require('./ruleset'),
            Anonymous = require('./anonymous'),
            utils = require('../utils'),
            LessError = require('../less-error');

//
// CSS @import node
//
// The general strategy here is that we don't want to wait
// for the parsing to be completed, before we start importing
// the file. That's because in the context of a browser,
// most of the time will be spent waiting for the server to respond.
//
// On creation, we push the import path to our import queue, though
// `import,push`, we also pass it a callback, which it'll call once
// the file has been fetched, and parsed.
//
        var Import = function (path, features, options, index, currentFileInfo, visibilityInfo) {
            this.options = options;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.path = path;
            this.features = features;
            this.allowRoot = true;

            if (this.options.less !== undefined || this.options.inline) {
                this.css = !this.options.less || this.options.inline;
            } else {
                var pathValue = this.getPath();
                if (pathValue && /[#\.\&\?]css([\?;].*)?$/.test(pathValue)) {
                    this.css = true;
                }
            }
            this.copyVisibilityInfo(visibilityInfo);
            this.setParent(this.features, this);
            this.setParent(this.path, this);
        };

//
// The actual import node doesn't return anything, when converted to CSS.
// The reason is that it's used at the evaluation stage, so that the rules
// it imports can be treated like any other rules.
//
// In `eval`, we make sure all Import nodes get evaluated, recursively, so
// we end up with a flat structure, which can easily be imported in the parent
// ruleset.
//
        Import.prototype = new Node();
        Import.prototype.type = 'Import';
        Import.prototype.accept = function (visitor) {
            if (this.features) {
                this.features = visitor.visit(this.features);
            }
            this.path = visitor.visit(this.path);
            if (!this.options.isPlugin && !this.options.inline && this.root) {
                this.root = visitor.visit(this.root);
            }
        };
        Import.prototype.genCSS = function (context, output) {
            if (this.css && this.path._fileInfo.reference === undefined) {
                output.add('@import ', this._fileInfo, this._index);
                this.path.genCSS(context, output);
                if (this.features) {
                    output.add(' ');
                    this.features.genCSS(context, output);
                }
                output.add(';');
            }
        };
        Import.prototype.getPath = function () {
            return (this.path instanceof URL) ?
                this.path.value.value : this.path.value;
        };
        Import.prototype.isVariableImport = function () {
            var path = this.path;
            if (path instanceof URL) {
                path = path.value;
            }
            if (path instanceof Quoted) {
                return path.containsVariables();
            }

            return true;
        };
        Import.prototype.evalForImport = function (context) {
            var path = this.path;

            if (path instanceof URL) {
                path = path.value;
            }

            return new Import(path.eval(context), this.features, this.options, this._index, this._fileInfo, this.visibilityInfo());
        };
        Import.prototype.evalPath = function (context) {
            var path = this.path.eval(context);
            var fileInfo = this._fileInfo;

            if (!(path instanceof URL)) {
                // Add the rootpath if the URL requires a rewrite
                var pathValue = path.value;
                if (fileInfo &&
                    pathValue &&
                    context.pathRequiresRewrite(pathValue)) {
                    path.value = context.rewritePath(pathValue, fileInfo.rootpath);
                } else {
                    path.value = context.normalizePath(path.value);
                }
            }

            return path;
        };
        Import.prototype.eval = function (context) {
            var result = this.doEval(context);
            if (this.options.reference || this.blocksVisibility()) {
                if (result.length || result.length === 0) {
                    result.forEach(function (node) {
                            node.addVisibilityBlock();
                        }
                    );
                } else {
                    result.addVisibilityBlock();
                }
            }
            return result;
        };
        Import.prototype.doEval = function (context) {
            var ruleset, registry,
                features = this.features && this.features.eval(context);

            if (this.options.isPlugin) {
                if (this.root && this.root.eval) {
                    try {
                        this.root.eval(context);
                    }
                    catch (e) {
                        e.message = 'Plugin error during evaluation';
                        throw new LessError(e, this.root.imports, this.root.filename);
                    }
                }
                registry = context.frames[0] && context.frames[0].functionRegistry;
                if ( registry && this.root && this.root.functions ) {
                    registry.addMultiple( this.root.functions );
                }

                return [];
            }

            if (this.skip) {
                if (typeof this.skip === 'function') {
                    this.skip = this.skip();
                }
                if (this.skip) {
                    return [];
                }
            }
            if (this.options.inline) {
                var contents = new Anonymous(this.root, 0,
                    {
                        filename: this.importedFilename,
                        reference: this.path._fileInfo && this.path._fileInfo.reference
                    }, true, true);

                return this.features ? new Media([contents], this.features.value) : [contents];
            } else if (this.css) {
                var newImport = new Import(this.evalPath(context), features, this.options, this._index);
                if (!newImport.css && this.error) {
                    throw this.error;
                }
                return newImport;
            } else {
                ruleset = new Ruleset(null, utils.copyArray(this.root.rules));
                ruleset.evalImports(context);

                return this.features ? new Media(ruleset.rules, this.features.value) : ruleset.rules;
            }
        };
        module.exports = Import;

    },{"../less-error":38,"../utils":89,"./anonymous":50,"./media":71,"./node":76,"./quoted":80,"./ruleset":81,"./url":85}],67:[function(require,module,exports){
        var tree = Object.create(null);

        tree.Node = require('./node');
        tree.Color = require('./color');
        tree.AtRule = require('./atrule');
        tree.DetachedRuleset = require('./detached-ruleset');
        tree.Operation = require('./operation');
        tree.Dimension = require('./dimension');
        tree.Unit = require('./unit');
        tree.Keyword = require('./keyword');
        tree.Variable = require('./variable');
        tree.Property = require('./property');
        tree.Ruleset = require('./ruleset');
        tree.Element = require('./element');
        tree.Attribute = require('./attribute');
        tree.Combinator = require('./combinator');
        tree.Selector = require('./selector');
        tree.Quoted = require('./quoted');
        tree.Expression = require('./expression');
        tree.Declaration = require('./declaration');
        tree.Call = require('./call');
        tree.URL = require('./url');
        tree.Import = require('./import');
        tree.mixin = {
            Call: require('./mixin-call'),
            Definition: require('./mixin-definition')
        };
        tree.Comment = require('./comment');
        tree.Anonymous = require('./anonymous');
        tree.Value = require('./value');
        tree.JavaScript = require('./javascript');
        tree.Assignment = require('./assignment');
        tree.Condition = require('./condition');
        tree.Paren = require('./paren');
        tree.Media = require('./media');
        tree.UnicodeDescriptor = require('./unicode-descriptor');
        tree.Negative = require('./negative');
        tree.Extend = require('./extend');
        tree.VariableCall = require('./variable-call');
        tree.NamespaceValue = require('./namespace-value');

        module.exports = tree;

    },{"./anonymous":50,"./assignment":51,"./atrule":52,"./attribute":53,"./call":54,"./color":55,"./combinator":56,"./comment":57,"./condition":58,"./declaration":60,"./detached-ruleset":61,"./dimension":62,"./element":63,"./expression":64,"./extend":65,"./import":66,"./javascript":68,"./keyword":70,"./media":71,"./mixin-call":72,"./mixin-definition":73,"./namespace-value":74,"./negative":75,"./node":76,"./operation":77,"./paren":78,"./property":79,"./quoted":80,"./ruleset":81,"./selector":82,"./unicode-descriptor":83,"./unit":84,"./url":85,"./value":86,"./variable":88,"./variable-call":87}],68:[function(require,module,exports){
        var JsEvalNode = require('./js-eval-node'),
            Dimension = require('./dimension'),
            Quoted = require('./quoted'),
            Anonymous = require('./anonymous');

        var JavaScript = function (string, escaped, index, currentFileInfo) {
            this.escaped = escaped;
            this.expression = string;
            this._index = index;
            this._fileInfo = currentFileInfo;
        };
        JavaScript.prototype = new JsEvalNode();
        JavaScript.prototype.type = 'JavaScript';
        JavaScript.prototype.eval = function(context) {
            var result = this.evaluateJavaScript(this.expression, context);
            var type = typeof result;

            if (type === 'number' && !isNaN(result)) {
                return new Dimension(result);
            } else if (type === 'string') {
                return new Quoted('"' + result + '"', result, this.escaped, this._index);
            } else if (Array.isArray(result)) {
                return new Anonymous(result.join(', '));
            } else {
                return new Anonymous(result);
            }
        };

        module.exports = JavaScript;

    },{"./anonymous":50,"./dimension":62,"./js-eval-node":69,"./quoted":80}],69:[function(require,module,exports){
        var Node = require('./node'),
            Variable = require('./variable');

        var JsEvalNode = function() {
        };
        JsEvalNode.prototype = new Node();

        JsEvalNode.prototype.evaluateJavaScript = function (expression, context) {
            var result,
                that = this,
                evalContext = {};

            if (!context.javascriptEnabled) {
                throw { message: 'Inline JavaScript is not enabled. Is it set in your options?',
                    filename: this.fileInfo().filename,
                    index: this.getIndex() };
            }

            expression = expression.replace(/@\{([\w-]+)\}/g, function (_, name) {
                return that.jsify(new Variable('@' + name, that.getIndex(), that.fileInfo()).eval(context));
            });

            try {
                expression = new Function('return (' + expression + ')');
            } catch (e) {
                throw { message: 'JavaScript evaluation error: ' + e.message + ' from `' + expression + '`' ,
                    filename: this.fileInfo().filename,
                    index: this.getIndex() };
            }

            var variables = context.frames[0].variables();
            for (var k in variables) {
                if (variables.hasOwnProperty(k)) {
                    /* jshint loopfunc:true */
                    evalContext[k.slice(1)] = {
                        value: variables[k].value,
                        toJS: function () {
                            return this.value.eval(context).toCSS();
                        }
                    };
                }
            }

            try {
                result = expression.call(evalContext);
            } catch (e) {
                throw { message: 'JavaScript evaluation error: \'' + e.name + ': ' + e.message.replace(/["]/g, '\'') + '\'' ,
                    filename: this.fileInfo().filename,
                    index: this.getIndex() };
            }
            return result;
        };
        JsEvalNode.prototype.jsify = function (obj) {
            if (Array.isArray(obj.value) && (obj.value.length > 1)) {
                return '[' + obj.value.map(function (v) { return v.toCSS(); }).join(', ') + ']';
            } else {
                return obj.toCSS();
            }
        };

        module.exports = JsEvalNode;

    },{"./node":76,"./variable":88}],70:[function(require,module,exports){
        var Node = require('./node');

        var Keyword = function (value) { this.value = value; };
        Keyword.prototype = new Node();
        Keyword.prototype.type = 'Keyword';
        Keyword.prototype.genCSS = function (context, output) {
            if (this.value === '%') { throw { type: 'Syntax', message: 'Invalid % without number' }; }
            output.add(this.value);
        };

        Keyword.True = new Keyword('true');
        Keyword.False = new Keyword('false');

        module.exports = Keyword;

    },{"./node":76}],71:[function(require,module,exports){
        var Ruleset = require('./ruleset'),
            Value = require('./value'),
            Selector = require('./selector'),
            Anonymous = require('./anonymous'),
            Expression = require('./expression'),
            AtRule = require('./atrule'),
            utils = require('../utils');

        var Media = function (value, features, index, currentFileInfo, visibilityInfo) {
            this._index = index;
            this._fileInfo = currentFileInfo;

            var selectors = (new Selector([], null, null, this._index, this._fileInfo)).createEmptySelectors();

            this.features = new Value(features);
            this.rules = [new Ruleset(selectors, value)];
            this.rules[0].allowImports = true;
            this.copyVisibilityInfo(visibilityInfo);
            this.allowRoot = true;
            this.setParent(selectors, this);
            this.setParent(this.features, this);
            this.setParent(this.rules, this);
        };
        Media.prototype = new AtRule();
        Media.prototype.type = 'Media';
        Media.prototype.isRulesetLike = function() { return true; };
        Media.prototype.accept = function (visitor) {
            if (this.features) {
                this.features = visitor.visit(this.features);
            }
            if (this.rules) {
                this.rules = visitor.visitArray(this.rules);
            }
        };
        Media.prototype.genCSS = function (context, output) {
            output.add('@media ', this._fileInfo, this._index);
            this.features.genCSS(context, output);
            this.outputRuleset(context, output, this.rules);
        };
        Media.prototype.eval = function (context) {
            if (!context.mediaBlocks) {
                context.mediaBlocks = [];
                context.mediaPath = [];
            }

            var media = new Media(null, [], this._index, this._fileInfo, this.visibilityInfo());
            if (this.debugInfo) {
                this.rules[0].debugInfo = this.debugInfo;
                media.debugInfo = this.debugInfo;
            }

            media.features = this.features.eval(context);

            context.mediaPath.push(media);
            context.mediaBlocks.push(media);

            this.rules[0].functionRegistry = context.frames[0].functionRegistry.inherit();
            context.frames.unshift(this.rules[0]);
            media.rules = [this.rules[0].eval(context)];
            context.frames.shift();

            context.mediaPath.pop();

            return context.mediaPath.length === 0 ? media.evalTop(context) :
                media.evalNested(context);
        };
        Media.prototype.evalTop = function (context) {
            var result = this;

            // Render all dependent Media blocks.
            if (context.mediaBlocks.length > 1) {
                var selectors = (new Selector([], null, null, this.getIndex(), this.fileInfo())).createEmptySelectors();
                result = new Ruleset(selectors, context.mediaBlocks);
                result.multiMedia = true;
                result.copyVisibilityInfo(this.visibilityInfo());
                this.setParent(result, this);
            }

            delete context.mediaBlocks;
            delete context.mediaPath;

            return result;
        };
        Media.prototype.evalNested = function (context) {
            var i, value,
                path = context.mediaPath.concat([this]);

            // Extract the media-query conditions separated with `,` (OR).
            for (i = 0; i < path.length; i++) {
                value = path[i].features instanceof Value ?
                    path[i].features.value : path[i].features;
                path[i] = Array.isArray(value) ? value : [value];
            }

            // Trace all permutations to generate the resulting media-query.
            //
            // (a, b and c) with nested (d, e) ->
            //    a and d
            //    a and e
            //    b and c and d
            //    b and c and e
            this.features = new Value(this.permute(path).map(function (path) {
                path = path.map(function (fragment) {
                    return fragment.toCSS ? fragment : new Anonymous(fragment);
                });

                for (i = path.length - 1; i > 0; i--) {
                    path.splice(i, 0, new Anonymous('and'));
                }

                return new Expression(path);
            }));
            this.setParent(this.features, this);

            // Fake a tree-node that doesn't output anything.
            return new Ruleset([], []);
        };
        Media.prototype.permute = function (arr) {
            if (arr.length === 0) {
                return [];
            } else if (arr.length === 1) {
                return arr[0];
            } else {
                var result = [];
                var rest = this.permute(arr.slice(1));
                for (var i = 0; i < rest.length; i++) {
                    for (var j = 0; j < arr[0].length; j++) {
                        result.push([arr[0][j]].concat(rest[i]));
                    }
                }
                return result;
            }
        };
        Media.prototype.bubbleSelectors = function (selectors) {
            if (!selectors) {
                return;
            }
            this.rules = [new Ruleset(utils.copyArray(selectors), [this.rules[0]])];
            this.setParent(this.rules, this);
        };
        module.exports = Media;

    },{"../utils":89,"./anonymous":50,"./atrule":52,"./expression":64,"./ruleset":81,"./selector":82,"./value":86}],72:[function(require,module,exports){
        var Node = require('./node'),
            Selector = require('./selector'),
            MixinDefinition = require('./mixin-definition'),
            defaultFunc = require('../functions/default');

        var MixinCall = function (elements, args, index, currentFileInfo, important) {
            this.selector = new Selector(elements);
            this.arguments = args || [];
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.important = important;
            this.allowRoot = true;
            this.setParent(this.selector, this);
        };
        MixinCall.prototype = new Node();
        MixinCall.prototype.type = 'MixinCall';
        MixinCall.prototype.accept = function (visitor) {
            if (this.selector) {
                this.selector = visitor.visit(this.selector);
            }
            if (this.arguments.length) {
                this.arguments = visitor.visitArray(this.arguments);
            }
        };
        MixinCall.prototype.eval = function (context) {
            var mixins, mixin, mixinPath, args = [], arg, argValue,
                rules = [], match = false, i, m, f, isRecursive, isOneFound,
                candidates = [], candidate, conditionResult = [], defaultResult, defFalseEitherCase = -1,
                defNone = 0, defTrue = 1, defFalse = 2, count, originalRuleset, noArgumentsFilter;

            this.selector = this.selector.eval(context);

            function calcDefGroup(mixin, mixinPath) {
                var f, p, namespace;

                for (f = 0; f < 2; f++) {
                    conditionResult[f] = true;
                    defaultFunc.value(f);
                    for (p = 0; p < mixinPath.length && conditionResult[f]; p++) {
                        namespace = mixinPath[p];
                        if (namespace.matchCondition) {
                            conditionResult[f] = conditionResult[f] && namespace.matchCondition(null, context);
                        }
                    }
                    if (mixin.matchCondition) {
                        conditionResult[f] = conditionResult[f] && mixin.matchCondition(args, context);
                    }
                }
                if (conditionResult[0] || conditionResult[1]) {
                    if (conditionResult[0] != conditionResult[1]) {
                        return conditionResult[1] ?
                            defTrue : defFalse;
                    }

                    return defNone;
                }
                return defFalseEitherCase;
            }

            for (i = 0; i < this.arguments.length; i++) {
                arg = this.arguments[i];
                argValue = arg.value.eval(context);
                if (arg.expand && Array.isArray(argValue.value)) {
                    argValue = argValue.value;
                    for (m = 0; m < argValue.length; m++) {
                        args.push({value: argValue[m]});
                    }
                } else {
                    args.push({name: arg.name, value: argValue});
                }
            }

            noArgumentsFilter = function(rule) {return rule.matchArgs(null, context);};

            for (i = 0; i < context.frames.length; i++) {
                if ((mixins = context.frames[i].find(this.selector, null, noArgumentsFilter)).length > 0) {
                    isOneFound = true;

                    // To make `default()` function independent of definition order we have two "subpasses" here.
                    // At first we evaluate each guard *twice* (with `default() == true` and `default() == false`),
                    // and build candidate list with corresponding flags. Then, when we know all possible matches,
                    // we make a final decision.

                    for (m = 0; m < mixins.length; m++) {
                        mixin = mixins[m].rule;
                        mixinPath = mixins[m].path;
                        isRecursive = false;
                        for (f = 0; f < context.frames.length; f++) {
                            if ((!(mixin instanceof MixinDefinition)) && mixin === (context.frames[f].originalRuleset || context.frames[f])) {
                                isRecursive = true;
                                break;
                            }
                        }
                        if (isRecursive) {
                            continue;
                        }

                        if (mixin.matchArgs(args, context)) {
                            candidate = {mixin: mixin, group: calcDefGroup(mixin, mixinPath)};

                            if (candidate.group !== defFalseEitherCase) {
                                candidates.push(candidate);
                            }

                            match = true;
                        }
                    }

                    defaultFunc.reset();

                    count = [0, 0, 0];
                    for (m = 0; m < candidates.length; m++) {
                        count[candidates[m].group]++;
                    }

                    if (count[defNone] > 0) {
                        defaultResult = defFalse;
                    } else {
                        defaultResult = defTrue;
                        if ((count[defTrue] + count[defFalse]) > 1) {
                            throw { type: 'Runtime',
                                message: 'Ambiguous use of `default()` found when matching for `' + this.format(args) + '`',
                                index: this.getIndex(), filename: this.fileInfo().filename };
                        }
                    }

                    for (m = 0; m < candidates.length; m++) {
                        candidate = candidates[m].group;
                        if ((candidate === defNone) || (candidate === defaultResult)) {
                            try {
                                mixin = candidates[m].mixin;
                                if (!(mixin instanceof MixinDefinition)) {
                                    originalRuleset = mixin.originalRuleset || mixin;
                                    mixin = new MixinDefinition('', [], mixin.rules, null, false, null, originalRuleset.visibilityInfo());
                                    mixin.originalRuleset = originalRuleset;
                                }
                                var newRules = mixin.evalCall(context, args, this.important).rules;
                                this._setVisibilityToReplacement(newRules);
                                Array.prototype.push.apply(rules, newRules);
                            } catch (e) {
                                throw { message: e.message, index: this.getIndex(), filename: this.fileInfo().filename, stack: e.stack };
                            }
                        }
                    }

                    if (match) {
                        return rules;
                    }
                }
            }
            if (isOneFound) {
                throw { type:    'Runtime',
                    message: 'No matching definition was found for `' + this.format(args) + '`',
                    index:   this.getIndex(), filename: this.fileInfo().filename };
            } else {
                throw { type:    'Name',
                    message: this.selector.toCSS().trim() + ' is undefined',
                    index:   this.getIndex(), filename: this.fileInfo().filename };
            }
        };

        MixinCall.prototype._setVisibilityToReplacement = function (replacement) {
            var i, rule;
            if (this.blocksVisibility()) {
                for (i = 0; i < replacement.length; i++) {
                    rule = replacement[i];
                    rule.addVisibilityBlock();
                }
            }
        };
        MixinCall.prototype.format = function (args) {
            return this.selector.toCSS().trim() + '(' +
                (args ? args.map(function (a) {
                    var argValue = '';
                    if (a.name) {
                        argValue += a.name + ':';
                    }
                    if (a.value.toCSS) {
                        argValue += a.value.toCSS();
                    } else {
                        argValue += '???';
                    }
                    return argValue;
                }).join(', ') : '') + ')';
        };
        module.exports = MixinCall;

    },{"../functions/default":25,"./mixin-definition":73,"./node":76,"./selector":82}],73:[function(require,module,exports){
        var Selector = require('./selector'),
            Element = require('./element'),
            Ruleset = require('./ruleset'),
            Declaration = require('./declaration'),
            DetachedRuleset = require('./detached-ruleset'),
            Expression = require('./expression'),
            contexts = require('../contexts'),
            utils = require('../utils');

        var Definition = function (name, params, rules, condition, variadic, frames, visibilityInfo) {
            this.name = name || 'anonymous mixin';
            this.selectors = [new Selector([new Element(null, name, false, this._index, this._fileInfo)])];
            this.params = params;
            this.condition = condition;
            this.variadic = variadic;
            this.arity = params.length;
            this.rules = rules;
            this._lookups = {};
            var optionalParameters = [];
            this.required = params.reduce(function (count, p) {
                if (!p.name || (p.name && !p.value)) {
                    return count + 1;
                }
                else {
                    optionalParameters.push(p.name);
                    return count;
                }
            }, 0);
            this.optionalParameters = optionalParameters;
            this.frames = frames;
            this.copyVisibilityInfo(visibilityInfo);
            this.allowRoot = true;
        };
        Definition.prototype = new Ruleset();
        Definition.prototype.type = 'MixinDefinition';
        Definition.prototype.evalFirst = true;
        Definition.prototype.accept = function (visitor) {
            if (this.params && this.params.length) {
                this.params = visitor.visitArray(this.params);
            }
            this.rules = visitor.visitArray(this.rules);
            if (this.condition) {
                this.condition = visitor.visit(this.condition);
            }
        };
        Definition.prototype.evalParams = function (context, mixinEnv, args, evaldArguments) {
            /* jshint boss:true */
            var frame = new Ruleset(null, null),
                varargs, arg,
                params = utils.copyArray(this.params),
                i, j, val, name, isNamedFound, argIndex, argsLength = 0;

            if (mixinEnv.frames && mixinEnv.frames[0] && mixinEnv.frames[0].functionRegistry) {
                frame.functionRegistry = mixinEnv.frames[0].functionRegistry.inherit();
            }
            mixinEnv = new contexts.Eval(mixinEnv, [frame].concat(mixinEnv.frames));

            if (args) {
                args = utils.copyArray(args);
                argsLength = args.length;

                for (i = 0; i < argsLength; i++) {
                    arg = args[i];
                    if (name = (arg && arg.name)) {
                        isNamedFound = false;
                        for (j = 0; j < params.length; j++) {
                            if (!evaldArguments[j] && name === params[j].name) {
                                evaldArguments[j] = arg.value.eval(context);
                                frame.prependRule(new Declaration(name, arg.value.eval(context)));
                                isNamedFound = true;
                                break;
                            }
                        }
                        if (isNamedFound) {
                            args.splice(i, 1);
                            i--;
                            continue;
                        } else {
                            throw { type: 'Runtime', message: 'Named argument for ' + this.name +
                                    ' ' + args[i].name + ' not found' };
                        }
                    }
                }
            }
            argIndex = 0;
            for (i = 0; i < params.length; i++) {
                if (evaldArguments[i]) { continue; }

                arg = args && args[argIndex];

                if (name = params[i].name) {
                    if (params[i].variadic) {
                        varargs = [];
                        for (j = argIndex; j < argsLength; j++) {
                            varargs.push(args[j].value.eval(context));
                        }
                        frame.prependRule(new Declaration(name, new Expression(varargs).eval(context)));
                    } else {
                        val = arg && arg.value;
                        if (val) {
                            // This was a mixin call, pass in a detached ruleset of it's eval'd rules
                            if (Array.isArray(val)) {
                                val = new DetachedRuleset(new Ruleset('', val));
                            }
                            else {
                                val = val.eval(context);
                            }
                        } else if (params[i].value) {
                            val = params[i].value.eval(mixinEnv);
                            frame.resetCache();
                        } else {
                            throw { type: 'Runtime', message: 'wrong number of arguments for ' + this.name +
                                    ' (' + argsLength + ' for ' + this.arity + ')' };
                        }

                        frame.prependRule(new Declaration(name, val));
                        evaldArguments[i] = val;
                    }
                }

                if (params[i].variadic && args) {
                    for (j = argIndex; j < argsLength; j++) {
                        evaldArguments[j] = args[j].value.eval(context);
                    }
                }
                argIndex++;
            }

            return frame;
        };
        Definition.prototype.makeImportant = function() {
            var rules = !this.rules ? this.rules : this.rules.map(function (r) {
                if (r.makeImportant) {
                    return r.makeImportant(true);
                } else {
                    return r;
                }
            });
            var result = new Definition(this.name, this.params, rules, this.condition, this.variadic, this.frames);
            return result;
        };
        Definition.prototype.eval = function (context) {
            return new Definition(this.name, this.params, this.rules, this.condition, this.variadic, this.frames || utils.copyArray(context.frames));
        };
        Definition.prototype.evalCall = function (context, args, important) {
            var _arguments = [],
                mixinFrames = this.frames ? this.frames.concat(context.frames) : context.frames,
                frame = this.evalParams(context, new contexts.Eval(context, mixinFrames), args, _arguments),
                rules, ruleset;

            frame.prependRule(new Declaration('@arguments', new Expression(_arguments).eval(context)));

            rules = utils.copyArray(this.rules);

            ruleset = new Ruleset(null, rules);
            ruleset.originalRuleset = this;
            ruleset = ruleset.eval(new contexts.Eval(context, [this, frame].concat(mixinFrames)));
            if (important) {
                ruleset = ruleset.makeImportant();
            }
            return ruleset;
        };
        Definition.prototype.matchCondition = function (args, context) {
            if (this.condition && !this.condition.eval(
                new contexts.Eval(context,
                    [this.evalParams(context, /* the parameter variables */
                        new contexts.Eval(context, this.frames ? this.frames.concat(context.frames) : context.frames), args, [])]
                        .concat(this.frames || []) // the parent namespace/mixin frames
                        .concat(context.frames)))) { // the current environment frames
                return false;
            }
            return true;
        };
        Definition.prototype.matchArgs = function (args, context) {
            var allArgsCnt = (args && args.length) || 0, len, optionalParameters = this.optionalParameters;
            var requiredArgsCnt = !args ? 0 : args.reduce(function (count, p) {
                if (optionalParameters.indexOf(p.name) < 0) {
                    return count + 1;
                } else {
                    return count;
                }
            }, 0);

            if (!this.variadic) {
                if (requiredArgsCnt < this.required) {
                    return false;
                }
                if (allArgsCnt > this.params.length) {
                    return false;
                }
            } else {
                if (requiredArgsCnt < (this.required - 1)) {
                    return false;
                }
            }

            // check patterns
            len = Math.min(requiredArgsCnt, this.arity);

            for (var i = 0; i < len; i++) {
                if (!this.params[i].name && !this.params[i].variadic) {
                    if (args[i].value.eval(context).toCSS() != this.params[i].value.eval(context).toCSS()) {
                        return false;
                    }
                }
            }
            return true;
        };
        module.exports = Definition;

    },{"../contexts":13,"../utils":89,"./declaration":60,"./detached-ruleset":61,"./element":63,"./expression":64,"./ruleset":81,"./selector":82}],74:[function(require,module,exports){
        var Node = require('./node'),
            Variable = require('./variable'),
            Ruleset = require('./ruleset'),
            Selector = require('./selector');

        var NamespaceValue = function (ruleCall, lookups, important, index, fileInfo) {
            this.value = ruleCall;
            this.lookups = lookups;
            this.important = important;
            this._index = index;
            this._fileInfo = fileInfo;
        };
        NamespaceValue.prototype = new Node();
        NamespaceValue.prototype.type = 'NamespaceValue';
        NamespaceValue.prototype.eval = function (context) {
            var i, j, name, rules = this.value.eval(context);

            for (i = 0; i < this.lookups.length; i++) {
                name = this.lookups[i];

                /**
                 * Eval'd DRs return rulesets.
                 * Eval'd mixins return rules, so let's make a ruleset if we need it.
                 * We need to do this because of late parsing of values
                 */
                if (Array.isArray(rules)) {
                    rules = new Ruleset([new Selector()], rules);
                }

                if (name === '') {
                    rules = rules.lastDeclaration();
                }
                else if (name.charAt(0) === '@') {
                    if (name.charAt(1) === '@') {
                        name = '@' + new Variable(name.substr(1)).eval(context).value;
                    }
                    if (rules.variables) {
                        rules = rules.variable(name);
                    }

                    if (!rules) {
                        throw { type: 'Name',
                            message: 'variable ' + name + ' not found',
                            filename: this.fileInfo().filename,
                            index: this.getIndex() };
                    }
                }
                else {
                    if (name.substring(0, 2) === '$@') {
                        name = '$' + new Variable(name.substr(1)).eval(context).value;
                    }
                    else {
                        name = name.charAt(0) === '$' ? name : '$' + name;
                    }
                    if (rules.properties) {
                        rules = rules.property(name);
                    }

                    if (!rules) {
                        throw { type: 'Name',
                            message: 'property "' + name.substr(1) + '" not found',
                            filename: this.fileInfo().filename,
                            index: this.getIndex() };
                    }
                    // Properties are an array of values, since a ruleset can have multiple props.
                    // We pick the last one (the "cascaded" value)
                    rules = rules[rules.length - 1];
                }

                if (rules.value) {
                    rules = rules.eval(context).value;
                }
                if (rules.ruleset) {
                    rules = rules.ruleset.eval(context);
                }
            }
            return rules;
        };
        module.exports = NamespaceValue;

    },{"./node":76,"./ruleset":81,"./selector":82,"./variable":88}],75:[function(require,module,exports){
        var Node = require('./node'),
            Operation = require('./operation'),
            Dimension = require('./dimension');

        var Negative = function (node) {
            this.value = node;
        };
        Negative.prototype = new Node();
        Negative.prototype.type = 'Negative';
        Negative.prototype.genCSS = function (context, output) {
            output.add('-');
            this.value.genCSS(context, output);
        };
        Negative.prototype.eval = function (context) {
            if (context.isMathOn()) {
                return (new Operation('*', [new Dimension(-1), this.value])).eval(context);
            }
            return new Negative(this.value.eval(context));
        };
        module.exports = Negative;

    },{"./dimension":62,"./node":76,"./operation":77}],76:[function(require,module,exports){
        var Node = function() {
            this.parent = null;
            this.visibilityBlocks = undefined;
            this.nodeVisible = undefined;
            this.rootNode = null;
            this.parsed = null;

            var self = this;
            Object.defineProperty(this, 'currentFileInfo', {
                get: function() { return self.fileInfo(); }
            });
            Object.defineProperty(this, 'index', {
                get: function() { return self.getIndex(); }
            });

        };
        Node.prototype.setParent = function(nodes, parent) {
            function set(node) {
                if (node && node instanceof Node) {
                    node.parent = parent;
                }
            }
            if (Array.isArray(nodes)) {
                nodes.forEach(set);
            }
            else {
                set(nodes);
            }
        };
        Node.prototype.getIndex = function() {
            return this._index || (this.parent && this.parent.getIndex()) || 0;
        };
        Node.prototype.fileInfo = function() {
            return this._fileInfo || (this.parent && this.parent.fileInfo()) || {};
        };
        Node.prototype.isRulesetLike = function() { return false; };
        Node.prototype.toCSS = function (context) {
            var strs = [];
            this.genCSS(context, {
                add: function(chunk, fileInfo, index) {
                    strs.push(chunk);
                },
                isEmpty: function () {
                    return strs.length === 0;
                }
            });
            return strs.join('');
        };
        Node.prototype.genCSS = function (context, output) {
            output.add(this.value);
        };
        Node.prototype.accept = function (visitor) {
            this.value = visitor.visit(this.value);
        };
        Node.prototype.eval = function () { return this; };
        Node.prototype._operate = function (context, op, a, b) {
            switch (op) {
                case '+': return a + b;
                case '-': return a - b;
                case '*': return a * b;
                case '/': return a / b;
            }
        };
        Node.prototype.fround = function(context, value) {
            var precision = context && context.numPrecision;
            // add "epsilon" to ensure numbers like 1.000000005 (represented as 1.000000004999...) are properly rounded:
            return (precision) ? Number((value + 2e-16).toFixed(precision)) : value;
        };
        Node.compare = function (a, b) {
            /* returns:
     -1: a < b
     0: a = b
     1: a > b
     and *any* other value for a != b (e.g. undefined, NaN, -2 etc.) */

            if ((a.compare) &&
                // for "symmetric results" force toCSS-based comparison
                // of Quoted or Anonymous if either value is one of those
                !(b.type === 'Quoted' || b.type === 'Anonymous')) {
                return a.compare(b);
            } else if (b.compare) {
                return -b.compare(a);
            } else if (a.type !== b.type) {
                return undefined;
            }

            a = a.value;
            b = b.value;
            if (!Array.isArray(a)) {
                return a === b ? 0 : undefined;
            }
            if (a.length !== b.length) {
                return undefined;
            }
            for (var i = 0; i < a.length; i++) {
                if (Node.compare(a[i], b[i]) !== 0) {
                    return undefined;
                }
            }
            return 0;
        };

        Node.numericCompare = function (a, b) {
            return a  <  b ? -1
                : a === b ?  0
                    : a  >  b ?  1 : undefined;
        };
// Returns true if this node represents root of ast imported by reference
        Node.prototype.blocksVisibility = function () {
            if (this.visibilityBlocks == null) {
                this.visibilityBlocks = 0;
            }
            return this.visibilityBlocks !== 0;
        };
        Node.prototype.addVisibilityBlock = function () {
            if (this.visibilityBlocks == null) {
                this.visibilityBlocks = 0;
            }
            this.visibilityBlocks = this.visibilityBlocks + 1;
        };
        Node.prototype.removeVisibilityBlock = function () {
            if (this.visibilityBlocks == null) {
                this.visibilityBlocks = 0;
            }
            this.visibilityBlocks = this.visibilityBlocks - 1;
        };
// Turns on node visibility - if called node will be shown in output regardless
// of whether it comes from import by reference or not
        Node.prototype.ensureVisibility = function () {
            this.nodeVisible = true;
        };
// Turns off node visibility - if called node will NOT be shown in output regardless
// of whether it comes from import by reference or not
        Node.prototype.ensureInvisibility = function () {
            this.nodeVisible = false;
        };
// return values:
// false - the node must not be visible
// true - the node must be visible
// undefined or null - the node has the same visibility as its parent
        Node.prototype.isVisible = function () {
            return this.nodeVisible;
        };
        Node.prototype.visibilityInfo = function() {
            return {
                visibilityBlocks: this.visibilityBlocks,
                nodeVisible: this.nodeVisible
            };
        };
        Node.prototype.copyVisibilityInfo = function(info) {
            if (!info) {
                return;
            }
            this.visibilityBlocks = info.visibilityBlocks;
            this.nodeVisible = info.nodeVisible;
        };
        module.exports = Node;

    },{}],77:[function(require,module,exports){
        var Node = require('./node'),
            Color = require('./color'),
            Dimension = require('./dimension'),
            MATH = require('../constants').Math;

        var Operation = function (op, operands, isSpaced) {
            this.op = op.trim();
            this.operands = operands;
            this.isSpaced = isSpaced;
        };
        Operation.prototype = new Node();
        Operation.prototype.type = 'Operation';
        Operation.prototype.accept = function (visitor) {
            this.operands = visitor.visit(this.operands);
        };
        Operation.prototype.eval = function (context) {
            var a = this.operands[0].eval(context),
                b = this.operands[1].eval(context),
                op;

            if (context.isMathOn(this.op)) {
                op = this.op === './' ? '/' : this.op;
                if (a instanceof Dimension && b instanceof Color) {
                    a = a.toColor();
                }
                if (b instanceof Dimension && a instanceof Color) {
                    b = b.toColor();
                }
                if (!a.operate) {
                    if (a instanceof Operation && a.op === '/' && context.math === MATH.PARENS_DIVISION) {
                        return new Operation(this.op, [a, b], this.isSpaced);
                    }
                    throw { type: 'Operation',
                        message: 'Operation on an invalid type' };
                }

                return a.operate(context, op, b);
            } else {
                return new Operation(this.op, [a, b], this.isSpaced);
            }
        };
        Operation.prototype.genCSS = function (context, output) {
            this.operands[0].genCSS(context, output);
            if (this.isSpaced) {
                output.add(' ');
            }
            output.add(this.op);
            if (this.isSpaced) {
                output.add(' ');
            }
            this.operands[1].genCSS(context, output);
        };

        module.exports = Operation;

    },{"../constants":12,"./color":55,"./dimension":62,"./node":76}],78:[function(require,module,exports){
        var Node = require('./node');

        var Paren = function (node) {
            this.value = node;
        };
        Paren.prototype = new Node();
        Paren.prototype.type = 'Paren';
        Paren.prototype.genCSS = function (context, output) {
            output.add('(');
            this.value.genCSS(context, output);
            output.add(')');
        };
        Paren.prototype.eval = function (context) {
            return new Paren(this.value.eval(context));
        };
        module.exports = Paren;

    },{"./node":76}],79:[function(require,module,exports){
        var Node = require('./node'),
            Declaration = require('./declaration');

        var Property = function (name, index, currentFileInfo) {
            this.name = name;
            this._index = index;
            this._fileInfo = currentFileInfo;
        };
        Property.prototype = new Node();
        Property.prototype.type = 'Property';
        Property.prototype.eval = function (context) {
            var property, name = this.name;
            // TODO: shorten this reference
            var mergeRules = context.pluginManager.less.visitors.ToCSSVisitor.prototype._mergeRules;

            if (this.evaluating) {
                throw { type: 'Name',
                    message: 'Recursive property reference for ' + name,
                    filename: this.fileInfo().filename,
                    index: this.getIndex() };
            }

            this.evaluating = true;

            property = this.find(context.frames, function (frame) {

                var v, vArr = frame.property(name);
                if (vArr) {
                    for (var i = 0; i < vArr.length; i++) {
                        v = vArr[i];

                        vArr[i] = new Declaration(v.name,
                            v.value,
                            v.important,
                            v.merge,
                            v.index,
                            v.currentFileInfo,
                            v.inline,
                            v.variable
                        );
                    }
                    mergeRules(vArr);

                    v = vArr[vArr.length - 1];
                    if (v.important) {
                        var importantScope = context.importantScope[context.importantScope.length - 1];
                        importantScope.important = v.important;
                    }
                    v = v.value.eval(context);
                    return v;
                }
            });
            if (property) {
                this.evaluating = false;
                return property;
            } else {
                throw { type: 'Name',
                    message: 'Property \'' + name + '\' is undefined',
                    filename: this.currentFileInfo.filename,
                    index: this.index };
            }
        };
        Property.prototype.find = function (obj, fun) {
            for (var i = 0, r; i < obj.length; i++) {
                r = fun.call(obj, obj[i]);
                if (r) { return r; }
            }
            return null;
        };
        module.exports = Property;

    },{"./declaration":60,"./node":76}],80:[function(require,module,exports){
        var Node = require('./node'),
            Variable = require('./variable'),
            Property = require('./property');

        var Quoted = function (str, content, escaped, index, currentFileInfo) {
            this.escaped = (escaped == null) ? true : escaped;
            this.value = content || '';
            this.quote = str.charAt(0);
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.variableRegex = /@\{([\w-]+)\}/g;
            this.propRegex = /\$\{([\w-]+)\}/g;
        };
        Quoted.prototype = new Node();
        Quoted.prototype.type = 'Quoted';
        Quoted.prototype.genCSS = function (context, output) {
            if (!this.escaped) {
                output.add(this.quote, this.fileInfo(), this.getIndex());
            }
            output.add(this.value);
            if (!this.escaped) {
                output.add(this.quote);
            }
        };
        Quoted.prototype.containsVariables = function() {
            return this.value.match(this.variableRegex);
        };
        Quoted.prototype.eval = function (context) {
            var that = this, value = this.value;
            var variableReplacement = function (_, name) {
                var v = new Variable('@' + name, that.getIndex(), that.fileInfo()).eval(context, true);
                return (v instanceof Quoted) ? v.value : v.toCSS();
            };
            var propertyReplacement = function (_, name) {
                var v = new Property('$' + name, that.getIndex(), that.fileInfo()).eval(context, true);
                return (v instanceof Quoted) ? v.value : v.toCSS();
            };
            function iterativeReplace(value, regexp, replacementFnc) {
                var evaluatedValue = value;
                do {
                    value = evaluatedValue;
                    evaluatedValue = value.replace(regexp, replacementFnc);
                } while (value !== evaluatedValue);
                return evaluatedValue;
            }
            value = iterativeReplace(value, this.variableRegex, variableReplacement);
            value = iterativeReplace(value, this.propRegex, propertyReplacement);
            return new Quoted(this.quote + value + this.quote, value, this.escaped, this.getIndex(), this.fileInfo());
        };
        Quoted.prototype.compare = function (other) {
            // when comparing quoted strings allow the quote to differ
            if (other.type === 'Quoted' && !this.escaped && !other.escaped) {
                return Node.numericCompare(this.value, other.value);
            } else {
                return other.toCSS && this.toCSS() === other.toCSS() ? 0 : undefined;
            }
        };
        module.exports = Quoted;

    },{"./node":76,"./property":79,"./variable":88}],81:[function(require,module,exports){
        var Node = require('./node'),
            Declaration = require('./declaration'),
            Keyword = require('./keyword'),
            Comment = require('./comment'),
            Paren = require('./paren'),
            Selector = require('./selector'),
            Element = require('./element'),
            Anonymous = require('./anonymous'),
            contexts = require('../contexts'),
            globalFunctionRegistry = require('../functions/function-registry'),
            defaultFunc = require('../functions/default'),
            getDebugInfo = require('./debug-info'),
            utils = require('../utils');

        var Ruleset = function (selectors, rules, strictImports, visibilityInfo) {
            this.selectors = selectors;
            this.rules = rules;
            this._lookups = {};
            this._variables = null;
            this._properties = null;
            this.strictImports = strictImports;
            this.copyVisibilityInfo(visibilityInfo);
            this.allowRoot = true;

            this.setParent(this.selectors, this);
            this.setParent(this.rules, this);

        };
        Ruleset.prototype = new Node();
        Ruleset.prototype.type = 'Ruleset';
        Ruleset.prototype.isRuleset = true;
        Ruleset.prototype.isRulesetLike = function() { return true; };
        Ruleset.prototype.accept = function (visitor) {
            if (this.paths) {
                this.paths = visitor.visitArray(this.paths, true);
            } else if (this.selectors) {
                this.selectors = visitor.visitArray(this.selectors);
            }
            if (this.rules && this.rules.length) {
                this.rules = visitor.visitArray(this.rules);
            }
        };
        Ruleset.prototype.eval = function (context) {
            var that = this, selectors, selCnt, selector, i, hasVariable, hasOnePassingSelector = false;

            if (this.selectors && (selCnt = this.selectors.length)) {
                selectors = new Array(selCnt);
                defaultFunc.error({
                    type: 'Syntax',
                    message: 'it is currently only allowed in parametric mixin guards,'
                });

                for (i = 0; i < selCnt; i++) {
                    selector = this.selectors[i].eval(context);
                    for (var j = 0; j < selector.elements.length; j++) {
                        if (selector.elements[j].isVariable) {
                            hasVariable = true;
                            break;
                        }
                    }
                    selectors[i] = selector;
                    if (selector.evaldCondition) {
                        hasOnePassingSelector = true;
                    }
                }

                if (hasVariable) {
                    var toParseSelectors = new Array(selCnt);
                    for (i = 0; i < selCnt; i++) {
                        selector = selectors[i];
                        toParseSelectors[i] = selector.toCSS(context);
                    }
                    this.parse.parseNode(
                        toParseSelectors.join(','),
                        ["selectors"],
                        selectors[0].getIndex(),
                        selectors[0].fileInfo(),
                        function(err, result) {
                            if (result) {
                                selectors = utils.flattenArray(result);
                            }
                        });
                }

                defaultFunc.reset();
            } else {
                hasOnePassingSelector = true;
            }

            var rules = this.rules ? utils.copyArray(this.rules) : null,
                ruleset = new Ruleset(selectors, rules, this.strictImports, this.visibilityInfo()),
                rule, subRule;

            ruleset.originalRuleset = this;
            ruleset.root = this.root;
            ruleset.firstRoot = this.firstRoot;
            ruleset.allowImports = this.allowImports;

            if (this.debugInfo) {
                ruleset.debugInfo = this.debugInfo;
            }

            if (!hasOnePassingSelector) {
                rules.length = 0;
            }

            // inherit a function registry from the frames stack when possible;
            // otherwise from the global registry
            ruleset.functionRegistry = (function (frames) {
                var i = 0,
                    n = frames.length,
                    found;
                for ( ; i !== n ; ++i ) {
                    found = frames[ i ].functionRegistry;
                    if ( found ) { return found; }
                }
                return globalFunctionRegistry;
            }(context.frames)).inherit();

            // push the current ruleset to the frames stack
            var ctxFrames = context.frames;
            ctxFrames.unshift(ruleset);

            // currrent selectors
            var ctxSelectors = context.selectors;
            if (!ctxSelectors) {
                context.selectors = ctxSelectors = [];
            }
            ctxSelectors.unshift(this.selectors);

            // Evaluate imports
            if (ruleset.root || ruleset.allowImports || !ruleset.strictImports) {
                ruleset.evalImports(context);
            }

            // Store the frames around mixin definitions,
            // so they can be evaluated like closures when the time comes.
            var rsRules = ruleset.rules;
            for (i = 0; (rule = rsRules[i]); i++) {
                if (rule.evalFirst) {
                    rsRules[i] = rule.eval(context);
                }
            }

            var mediaBlockCount = (context.mediaBlocks && context.mediaBlocks.length) || 0;

            // Evaluate mixin calls.
            for (i = 0; (rule = rsRules[i]); i++) {
                if (rule.type === 'MixinCall') {
                    /* jshint loopfunc:true */
                    rules = rule.eval(context).filter(function(r) {
                        if ((r instanceof Declaration) && r.variable) {
                            // do not pollute the scope if the variable is
                            // already there. consider returning false here
                            // but we need a way to "return" variable from mixins
                            return !(ruleset.variable(r.name));
                        }
                        return true;
                    });
                    rsRules.splice.apply(rsRules, [i, 1].concat(rules));
                    i += rules.length - 1;
                    ruleset.resetCache();
                } else if (rule.type ===  'VariableCall') {
                    /* jshint loopfunc:true */
                    rules = rule.eval(context).rules.filter(function(r) {
                        if ((r instanceof Declaration) && r.variable) {
                            // do not pollute the scope at all
                            return false;
                        }
                        return true;
                    });
                    rsRules.splice.apply(rsRules, [i, 1].concat(rules));
                    i += rules.length - 1;
                    ruleset.resetCache();
                }
            }

            // Evaluate everything else
            for (i = 0; (rule = rsRules[i]); i++) {
                if (!rule.evalFirst) {
                    rsRules[i] = rule = rule.eval ? rule.eval(context) : rule;
                }
            }

            // Evaluate everything else
            for (i = 0; (rule = rsRules[i]); i++) {
                // for rulesets, check if it is a css guard and can be removed
                if (rule instanceof Ruleset && rule.selectors && rule.selectors.length === 1) {
                    // check if it can be folded in (e.g. & where)
                    if (rule.selectors[0] && rule.selectors[0].isJustParentSelector()) {
                        rsRules.splice(i--, 1);

                        for (var j = 0; (subRule = rule.rules[j]); j++) {
                            if (subRule instanceof Node) {
                                subRule.copyVisibilityInfo(rule.visibilityInfo());
                                if (!(subRule instanceof Declaration) || !subRule.variable) {
                                    rsRules.splice(++i, 0, subRule);
                                }
                            }
                        }
                    }
                }
            }

            // Pop the stack
            ctxFrames.shift();
            ctxSelectors.shift();

            if (context.mediaBlocks) {
                for (i = mediaBlockCount; i < context.mediaBlocks.length; i++) {
                    context.mediaBlocks[i].bubbleSelectors(selectors);
                }
            }

            return ruleset;
        };
        Ruleset.prototype.evalImports = function(context) {
            var rules = this.rules, i, importRules;
            if (!rules) { return; }

            for (i = 0; i < rules.length; i++) {
                if (rules[i].type === 'Import') {
                    importRules = rules[i].eval(context);
                    if (importRules && (importRules.length || importRules.length === 0)) {
                        rules.splice.apply(rules, [i, 1].concat(importRules));
                        i += importRules.length - 1;
                    } else {
                        rules.splice(i, 1, importRules);
                    }
                    this.resetCache();
                }
            }
        };
        Ruleset.prototype.makeImportant = function() {
            var result = new Ruleset(this.selectors, this.rules.map(function (r) {
                if (r.makeImportant) {
                    return r.makeImportant();
                } else {
                    return r;
                }
            }), this.strictImports, this.visibilityInfo());

            return result;
        };
        Ruleset.prototype.matchArgs = function (args) {
            return !args || args.length === 0;
        };
// lets you call a css selector with a guard
        Ruleset.prototype.matchCondition = function (args, context) {
            var lastSelector = this.selectors[this.selectors.length - 1];
            if (!lastSelector.evaldCondition) {
                return false;
            }
            if (lastSelector.condition &&
                !lastSelector.condition.eval(
                    new contexts.Eval(context,
                        context.frames))) {
                return false;
            }
            return true;
        };
        Ruleset.prototype.resetCache = function () {
            this._rulesets = null;
            this._variables = null;
            this._properties = null;
            this._lookups = {};
        };
        Ruleset.prototype.variables = function () {
            if (!this._variables) {
                this._variables = !this.rules ? {} : this.rules.reduce(function (hash, r) {
                    if (r instanceof Declaration && r.variable === true) {
                        hash[r.name] = r;
                    }
                    // when evaluating variables in an import statement, imports have not been eval'd
                    // so we need to go inside import statements.
                    // guard against root being a string (in the case of inlined less)
                    if (r.type === 'Import' && r.root && r.root.variables) {
                        var vars = r.root.variables();
                        for (var name in vars) {
                            if (vars.hasOwnProperty(name)) {
                                hash[name] = r.root.variable(name);
                            }
                        }
                    }
                    return hash;
                }, {});
            }
            return this._variables;
        };
        Ruleset.prototype.properties = function () {
            if (!this._properties) {
                this._properties = !this.rules ? {} : this.rules.reduce(function (hash, r) {
                    if (r instanceof Declaration && r.variable !== true) {
                        var name = (r.name.length === 1) && (r.name[0] instanceof Keyword) ?
                            r.name[0].value : r.name;
                        // Properties don't overwrite as they can merge
                        if (!hash['$' + name]) {
                            hash['$' + name] = [ r ];
                        }
                        else {
                            hash['$' + name].push(r);
                        }
                    }
                    return hash;
                }, {});
            }
            return this._properties;
        };
        Ruleset.prototype.variable = function (name) {
            var decl = this.variables()[name];
            if (decl) {
                return this.parseValue(decl);
            }
        };
        Ruleset.prototype.property = function (name) {
            var decl = this.properties()[name];
            if (decl) {
                return this.parseValue(decl);
            }
        };
        Ruleset.prototype.lastDeclaration = function () {
            for (var i = this.rules.length; i > 0; i--) {
                var decl = this.rules[i - 1];
                if (decl instanceof Declaration) {
                    return this.parseValue(decl);
                }
            }
        };
        Ruleset.prototype.parseValue = function(toParse) {
            var self = this;
            function transformDeclaration(decl) {
                if (decl.value instanceof Anonymous && !decl.parsed) {
                    if (typeof decl.value.value === 'string') {
                        this.parse.parseNode(
                            decl.value.value,
                            ['value', 'important'],
                            decl.value.getIndex(),
                            decl.fileInfo(),
                            function(err, result) {
                                if (err) {
                                    decl.parsed = true;
                                }
                                if (result) {
                                    decl.value = result[0];
                                    decl.important = result[1] || '';
                                    decl.parsed = true;
                                }
                            });
                    } else {
                        decl.parsed = true;
                    }

                    return decl;
                }
                else {
                    return decl;
                }
            }
            if (!Array.isArray(toParse)) {
                return transformDeclaration.call(self, toParse);
            }
            else {
                var nodes = [];
                toParse.forEach(function(n) {
                    nodes.push(transformDeclaration.call(self, n));
                });
                return nodes;
            }
        };
        Ruleset.prototype.rulesets = function () {
            if (!this.rules) { return []; }

            var filtRules = [], rules = this.rules,
                i, rule;

            for (i = 0; (rule = rules[i]); i++) {
                if (rule.isRuleset) {
                    filtRules.push(rule);
                }
            }

            return filtRules;
        };
        Ruleset.prototype.prependRule = function (rule) {
            var rules = this.rules;
            if (rules) {
                rules.unshift(rule);
            } else {
                this.rules = [ rule ];
            }
            this.setParent(rule, this);
        };
        Ruleset.prototype.find = function (selector, self, filter) {
            self = self || this;
            var rules = [], match, foundMixins,
                key = selector.toCSS();

            if (key in this._lookups) { return this._lookups[key]; }

            this.rulesets().forEach(function (rule) {
                if (rule !== self) {
                    for (var j = 0; j < rule.selectors.length; j++) {
                        match = selector.match(rule.selectors[j]);
                        if (match) {
                            if (selector.elements.length > match) {
                                if (!filter || filter(rule)) {
                                    foundMixins = rule.find(new Selector(selector.elements.slice(match)), self, filter);
                                    for (var i = 0; i < foundMixins.length; ++i) {
                                        foundMixins[i].path.push(rule);
                                    }
                                    Array.prototype.push.apply(rules, foundMixins);
                                }
                            } else {
                                rules.push({ rule: rule, path: []});
                            }
                            break;
                        }
                    }
                }
            });
            this._lookups[key] = rules;
            return rules;
        };
        Ruleset.prototype.genCSS = function (context, output) {
            var i, j,
                charsetRuleNodes = [],
                ruleNodes = [],
                debugInfo,     // Line number debugging
                rule,
                path;

            context.tabLevel = (context.tabLevel || 0);

            if (!this.root) {
                context.tabLevel++;
            }

            var tabRuleStr = context.compress ? '' : Array(context.tabLevel + 1).join('  '),
                tabSetStr = context.compress ? '' : Array(context.tabLevel).join('  '),
                sep;

            var charsetNodeIndex = 0;
            var importNodeIndex = 0;
            for (i = 0; (rule = this.rules[i]); i++) {
                if (rule instanceof Comment) {
                    if (importNodeIndex === i) {
                        importNodeIndex++;
                    }
                    ruleNodes.push(rule);
                } else if (rule.isCharset && rule.isCharset()) {
                    ruleNodes.splice(charsetNodeIndex, 0, rule);
                    charsetNodeIndex++;
                    importNodeIndex++;
                } else if (rule.type === 'Import') {
                    ruleNodes.splice(importNodeIndex, 0, rule);
                    importNodeIndex++;
                } else {
                    ruleNodes.push(rule);
                }
            }
            ruleNodes = charsetRuleNodes.concat(ruleNodes);

            // If this is the root node, we don't render
            // a selector, or {}.
            if (!this.root) {
                debugInfo = getDebugInfo(context, this, tabSetStr);

                if (debugInfo) {
                    output.add(debugInfo);
                    output.add(tabSetStr);
                }

                var paths = this.paths, pathCnt = paths.length,
                    pathSubCnt;

                sep = context.compress ? ',' : (',\n' + tabSetStr);

                for (i = 0; i < pathCnt; i++) {
                    path = paths[i];
                    if (!(pathSubCnt = path.length)) { continue; }
                    if (i > 0) { output.add(sep); }

                    context.firstSelector = true;
                    path[0].genCSS(context, output);

                    context.firstSelector = false;
                    for (j = 1; j < pathSubCnt; j++) {
                        path[j].genCSS(context, output);
                    }
                }

                output.add((context.compress ? '{' : ' {\n') + tabRuleStr);
            }

            // Compile rules and rulesets
            for (i = 0; (rule = ruleNodes[i]); i++) {

                if (i + 1 === ruleNodes.length) {
                    context.lastRule = true;
                }

                var currentLastRule = context.lastRule;
                if (rule.isRulesetLike(rule)) {
                    context.lastRule = false;
                }

                if (rule.genCSS) {
                    rule.genCSS(context, output);
                } else if (rule.value) {
                    output.add(rule.value.toString());
                }

                context.lastRule = currentLastRule;

                if (!context.lastRule && rule.isVisible()) {
                    output.add(context.compress ? '' : ('\n' + tabRuleStr));
                } else {
                    context.lastRule = false;
                }
            }

            if (!this.root) {
                output.add((context.compress ? '}' : '\n' + tabSetStr + '}'));
                context.tabLevel--;
            }

            if (!output.isEmpty() && !context.compress && this.firstRoot) {
                output.add('\n');
            }
        };

        Ruleset.prototype.joinSelectors = function (paths, context, selectors) {
            for (var s = 0; s < selectors.length; s++) {
                this.joinSelector(paths, context, selectors[s]);
            }
        };

        Ruleset.prototype.joinSelector = function (paths, context, selector) {

            function createParenthesis(elementsToPak, originalElement) {
                var replacementParen, j;
                if (elementsToPak.length === 0) {
                    replacementParen = new Paren(elementsToPak[0]);
                } else {
                    var insideParent = new Array(elementsToPak.length);
                    for (j = 0; j < elementsToPak.length; j++) {
                        insideParent[j] = new Element(
                            null,
                            elementsToPak[j],
                            originalElement.isVariable,
                            originalElement._index,
                            originalElement._fileInfo
                        );
                    }
                    replacementParen = new Paren(new Selector(insideParent));
                }
                return replacementParen;
            }

            function createSelector(containedElement, originalElement) {
                var element, selector;
                element = new Element(null, containedElement, originalElement.isVariable, originalElement._index, originalElement._fileInfo);
                selector = new Selector([element]);
                return selector;
            }

            // joins selector path from `beginningPath` with selector path in `addPath`
            // `replacedElement` contains element that is being replaced by `addPath`
            // returns concatenated path
            function addReplacementIntoPath(beginningPath, addPath, replacedElement, originalSelector) {
                var newSelectorPath, lastSelector, newJoinedSelector;
                // our new selector path
                newSelectorPath = [];

                // construct the joined selector - if & is the first thing this will be empty,
                // if not newJoinedSelector will be the last set of elements in the selector
                if (beginningPath.length > 0) {
                    newSelectorPath = utils.copyArray(beginningPath);
                    lastSelector = newSelectorPath.pop();
                    newJoinedSelector = originalSelector.createDerived(utils.copyArray(lastSelector.elements));
                }
                else {
                    newJoinedSelector = originalSelector.createDerived([]);
                }

                if (addPath.length > 0) {
                    // /deep/ is a CSS4 selector - (removed, so should deprecate)
                    // that is valid without anything in front of it
                    // so if the & does not have a combinator that is "" or " " then
                    // and there is a combinator on the parent, then grab that.
                    // this also allows + a { & .b { .a & { ... though not sure why you would want to do that
                    var combinator = replacedElement.combinator, parentEl = addPath[0].elements[0];
                    if (combinator.emptyOrWhitespace && !parentEl.combinator.emptyOrWhitespace) {
                        combinator = parentEl.combinator;
                    }
                    // join the elements so far with the first part of the parent
                    newJoinedSelector.elements.push(new Element(
                        combinator,
                        parentEl.value,
                        replacedElement.isVariable,
                        replacedElement._index,
                        replacedElement._fileInfo
                    ));
                    newJoinedSelector.elements = newJoinedSelector.elements.concat(addPath[0].elements.slice(1));
                }

                // now add the joined selector - but only if it is not empty
                if (newJoinedSelector.elements.length !== 0) {
                    newSelectorPath.push(newJoinedSelector);
                }

                // put together the parent selectors after the join (e.g. the rest of the parent)
                if (addPath.length > 1) {
                    var restOfPath = addPath.slice(1);
                    restOfPath = restOfPath.map(function (selector) {
                        return selector.createDerived(selector.elements, []);
                    });
                    newSelectorPath = newSelectorPath.concat(restOfPath);
                }
                return newSelectorPath;
            }

            // joins selector path from `beginningPath` with every selector path in `addPaths` array
            // `replacedElement` contains element that is being replaced by `addPath`
            // returns array with all concatenated paths
            function addAllReplacementsIntoPath( beginningPath, addPaths, replacedElement, originalSelector, result) {
                var j;
                for (j = 0; j < beginningPath.length; j++) {
                    var newSelectorPath = addReplacementIntoPath(beginningPath[j], addPaths, replacedElement, originalSelector);
                    result.push(newSelectorPath);
                }
                return result;
            }

            function mergeElementsOnToSelectors(elements, selectors) {
                var i, sel;

                if (elements.length === 0) {
                    return ;
                }
                if (selectors.length === 0) {
                    selectors.push([ new Selector(elements) ]);
                    return;
                }

                for (i = 0; (sel = selectors[i]); i++) {
                    // if the previous thing in sel is a parent this needs to join on to it
                    if (sel.length > 0) {
                        sel[sel.length - 1] = sel[sel.length - 1].createDerived(sel[sel.length - 1].elements.concat(elements));
                    }
                    else {
                        sel.push(new Selector(elements));
                    }
                }
            }

            // replace all parent selectors inside `inSelector` by content of `context` array
            // resulting selectors are returned inside `paths` array
            // returns true if `inSelector` contained at least one parent selector
            function replaceParentSelector(paths, context, inSelector) {
                // The paths are [[Selector]]
                // The first list is a list of comma separated selectors
                // The inner list is a list of inheritance separated selectors
                // e.g.
                // .a, .b {
                //   .c {
                //   }
                // }
                // == [[.a] [.c]] [[.b] [.c]]
                //
                var i, j, k, currentElements, newSelectors, selectorsMultiplied, sel, el, hadParentSelector = false, length, lastSelector;
                function findNestedSelector(element) {
                    var maybeSelector;
                    if (!(element.value instanceof Paren)) {
                        return null;
                    }

                    maybeSelector = element.value.value;
                    if (!(maybeSelector instanceof Selector)) {
                        return null;
                    }

                    return maybeSelector;
                }

                // the elements from the current selector so far
                currentElements = [];
                // the current list of new selectors to add to the path.
                // We will build it up. We initiate it with one empty selector as we "multiply" the new selectors
                // by the parents
                newSelectors = [
                    []
                ];

                for (i = 0; (el = inSelector.elements[i]); i++) {
                    // non parent reference elements just get added
                    if (el.value !== '&') {
                        var nestedSelector = findNestedSelector(el);
                        if (nestedSelector != null) {
                            // merge the current list of non parent selector elements
                            // on to the current list of selectors to add
                            mergeElementsOnToSelectors(currentElements, newSelectors);

                            var nestedPaths = [], replaced, replacedNewSelectors = [];
                            replaced = replaceParentSelector(nestedPaths, context, nestedSelector);
                            hadParentSelector = hadParentSelector || replaced;
                            // the nestedPaths array should have only one member - replaceParentSelector does not multiply selectors
                            for (k = 0; k < nestedPaths.length; k++) {
                                var replacementSelector = createSelector(createParenthesis(nestedPaths[k], el), el);
                                addAllReplacementsIntoPath(newSelectors, [replacementSelector], el, inSelector, replacedNewSelectors);
                            }
                            newSelectors = replacedNewSelectors;
                            currentElements = [];

                        } else {
                            currentElements.push(el);
                        }

                    } else {
                        hadParentSelector = true;
                        // the new list of selectors to add
                        selectorsMultiplied = [];

                        // merge the current list of non parent selector elements
                        // on to the current list of selectors to add
                        mergeElementsOnToSelectors(currentElements, newSelectors);

                        // loop through our current selectors
                        for (j = 0; j < newSelectors.length; j++) {
                            sel = newSelectors[j];
                            // if we don't have any parent paths, the & might be in a mixin so that it can be used
                            // whether there are parents or not
                            if (context.length === 0) {
                                // the combinator used on el should now be applied to the next element instead so that
                                // it is not lost
                                if (sel.length > 0) {
                                    sel[0].elements.push(new Element(el.combinator, '', el.isVariable, el._index, el._fileInfo));
                                }
                                selectorsMultiplied.push(sel);
                            }
                            else {
                                // and the parent selectors
                                for (k = 0; k < context.length; k++) {
                                    // We need to put the current selectors
                                    // then join the last selector's elements on to the parents selectors
                                    var newSelectorPath = addReplacementIntoPath(sel, context[k], el, inSelector);
                                    // add that to our new set of selectors
                                    selectorsMultiplied.push(newSelectorPath);
                                }
                            }
                        }

                        // our new selectors has been multiplied, so reset the state
                        newSelectors = selectorsMultiplied;
                        currentElements = [];
                    }
                }

                // if we have any elements left over (e.g. .a& .b == .b)
                // add them on to all the current selectors
                mergeElementsOnToSelectors(currentElements, newSelectors);

                for (i = 0; i < newSelectors.length; i++) {
                    length = newSelectors[i].length;
                    if (length > 0) {
                        paths.push(newSelectors[i]);
                        lastSelector = newSelectors[i][length - 1];
                        newSelectors[i][length - 1] = lastSelector.createDerived(lastSelector.elements, inSelector.extendList);
                    }
                }

                return hadParentSelector;
            }

            function deriveSelector(visibilityInfo, deriveFrom) {
                var newSelector = deriveFrom.createDerived(deriveFrom.elements, deriveFrom.extendList, deriveFrom.evaldCondition);
                newSelector.copyVisibilityInfo(visibilityInfo);
                return newSelector;
            }

            // joinSelector code follows
            var i, newPaths, hadParentSelector;

            newPaths = [];
            hadParentSelector = replaceParentSelector(newPaths, context, selector);

            if (!hadParentSelector) {
                if (context.length > 0) {
                    newPaths = [];
                    for (i = 0; i < context.length; i++) {

                        var concatenated = context[i].map(deriveSelector.bind(this, selector.visibilityInfo()));

                        concatenated.push(selector);
                        newPaths.push(concatenated);
                    }
                }
                else {
                    newPaths = [[selector]];
                }
            }

            for (i = 0; i < newPaths.length; i++) {
                paths.push(newPaths[i]);
            }

        };
        module.exports = Ruleset;

    },{"../contexts":13,"../functions/default":25,"../functions/function-registry":27,"../utils":89,"./anonymous":50,"./comment":57,"./debug-info":59,"./declaration":60,"./element":63,"./keyword":70,"./node":76,"./paren":78,"./selector":82}],82:[function(require,module,exports){
        var Node = require('./node'),
            Element = require('./element'),
            LessError = require('../less-error');

        var Selector = function (elements, extendList, condition, index, currentFileInfo, visibilityInfo) {
            this.extendList = extendList;
            this.condition = condition;
            this.evaldCondition = !condition;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.elements = this.getElements(elements);
            this.mixinElements_ = undefined;
            this.copyVisibilityInfo(visibilityInfo);
            this.setParent(this.elements, this);
        };
        Selector.prototype = new Node();
        Selector.prototype.type = 'Selector';
        Selector.prototype.accept = function (visitor) {
            if (this.elements) {
                this.elements = visitor.visitArray(this.elements);
            }
            if (this.extendList) {
                this.extendList = visitor.visitArray(this.extendList);
            }
            if (this.condition) {
                this.condition = visitor.visit(this.condition);
            }
        };
        Selector.prototype.createDerived = function(elements, extendList, evaldCondition) {
            elements = this.getElements(elements);
            var newSelector = new Selector(elements, extendList || this.extendList,
                null, this.getIndex(), this.fileInfo(), this.visibilityInfo());
            newSelector.evaldCondition = (evaldCondition != null) ? evaldCondition : this.evaldCondition;
            newSelector.mediaEmpty = this.mediaEmpty;
            return newSelector;
        };
        Selector.prototype.getElements = function(els) {
            if (!els) {
                return [new Element('', '&', false, this._index, this._fileInfo)];
            }
            if (typeof els === 'string') {
                this.parse.parseNode(
                    els,
                    ['selector'],
                    this._index,
                    this._fileInfo,
                    function(err, result) {
                        if (err) {
                            throw new LessError({
                                index: err.index,
                                message: err.message
                            }, this.parse.imports, this._fileInfo.filename);
                        }
                        els = result[0].elements;
                    });
            }
            return els;
        };
        Selector.prototype.createEmptySelectors = function() {
            var el = new Element('', '&', false, this._index, this._fileInfo),
                sels = [new Selector([el], null, null, this._index, this._fileInfo)];
            sels[0].mediaEmpty = true;
            return sels;
        };
        Selector.prototype.match = function (other) {
            var elements = this.elements,
                len = elements.length,
                olen, i;

            other = other.mixinElements();
            olen = other.length;
            if (olen === 0 || len < olen) {
                return 0;
            } else {
                for (i = 0; i < olen; i++) {
                    if (elements[i].value !== other[i]) {
                        return 0;
                    }
                }
            }

            return olen; // return number of matched elements
        };
        Selector.prototype.mixinElements = function() {
            if (this.mixinElements_) {
                return this.mixinElements_;
            }

            var elements = this.elements.map( function(v) {
                return v.combinator.value + (v.value.value || v.value);
            }).join('').match(/[,&#\*\.\w-]([\w-]|(\\.))*/g);

            if (elements) {
                if (elements[0] === '&') {
                    elements.shift();
                }
            } else {
                elements = [];
            }

            return (this.mixinElements_ = elements);
        };
        Selector.prototype.isJustParentSelector = function() {
            return !this.mediaEmpty &&
                this.elements.length === 1 &&
                this.elements[0].value === '&' &&
                (this.elements[0].combinator.value === ' ' || this.elements[0].combinator.value === '');
        };
        Selector.prototype.eval = function (context) {
            var evaldCondition = this.condition && this.condition.eval(context),
                elements = this.elements, extendList = this.extendList;

            elements = elements && elements.map(function (e) { return e.eval(context); });
            extendList = extendList && extendList.map(function(extend) { return extend.eval(context); });

            return this.createDerived(elements, extendList, evaldCondition);
        };
        Selector.prototype.genCSS = function (context, output) {
            var i, element;
            if ((!context || !context.firstSelector) && this.elements[0].combinator.value === '') {
                output.add(' ', this.fileInfo(), this.getIndex());
            }
            for (i = 0; i < this.elements.length; i++) {
                element = this.elements[i];
                element.genCSS(context, output);
            }
        };
        Selector.prototype.getIsOutput = function() {
            return this.evaldCondition;
        };
        module.exports = Selector;

    },{"../less-error":38,"./element":63,"./node":76}],83:[function(require,module,exports){
        var Node = require('./node');

        var UnicodeDescriptor = function (value) {
            this.value = value;
        };
        UnicodeDescriptor.prototype = new Node();
        UnicodeDescriptor.prototype.type = 'UnicodeDescriptor';

        module.exports = UnicodeDescriptor;

    },{"./node":76}],84:[function(require,module,exports){
        var Node = require('./node'),
            unitConversions = require('../data/unit-conversions'),
            utils = require('../utils');

        var Unit = function (numerator, denominator, backupUnit) {
            this.numerator = numerator ? utils.copyArray(numerator).sort() : [];
            this.denominator = denominator ? utils.copyArray(denominator).sort() : [];
            if (backupUnit) {
                this.backupUnit = backupUnit;
            } else if (numerator && numerator.length) {
                this.backupUnit = numerator[0];
            }
        };

        Unit.prototype = new Node();
        Unit.prototype.type = 'Unit';
        Unit.prototype.clone = function () {
            return new Unit(utils.copyArray(this.numerator), utils.copyArray(this.denominator), this.backupUnit);
        };
        Unit.prototype.genCSS = function (context, output) {
            // Dimension checks the unit is singular and throws an error if in strict math mode.
            var strictUnits = context && context.strictUnits;
            if (this.numerator.length === 1) {
                output.add(this.numerator[0]); // the ideal situation
            } else if (!strictUnits && this.backupUnit) {
                output.add(this.backupUnit);
            } else if (!strictUnits && this.denominator.length) {
                output.add(this.denominator[0]);
            }
        };
        Unit.prototype.toString = function () {
            var i, returnStr = this.numerator.join('*');
            for (i = 0; i < this.denominator.length; i++) {
                returnStr += '/' + this.denominator[i];
            }
            return returnStr;
        };
        Unit.prototype.compare = function (other) {
            return this.is(other.toString()) ? 0 : undefined;
        };
        Unit.prototype.is = function (unitString) {
            return this.toString().toUpperCase() === unitString.toUpperCase();
        };
        Unit.prototype.isLength = function () {
            return RegExp('^(px|em|ex|ch|rem|in|cm|mm|pc|pt|ex|vw|vh|vmin|vmax)$', 'gi').test(this.toCSS());
        };
        Unit.prototype.isEmpty = function () {
            return this.numerator.length === 0 && this.denominator.length === 0;
        };
        Unit.prototype.isSingular = function() {
            return this.numerator.length <= 1 && this.denominator.length === 0;
        };
        Unit.prototype.map = function(callback) {
            var i;

            for (i = 0; i < this.numerator.length; i++) {
                this.numerator[i] = callback(this.numerator[i], false);
            }

            for (i = 0; i < this.denominator.length; i++) {
                this.denominator[i] = callback(this.denominator[i], true);
            }
        };
        Unit.prototype.usedUnits = function() {
            var group, result = {}, mapUnit, groupName;

            mapUnit = function (atomicUnit) {
                /* jshint loopfunc:true */
                if (group.hasOwnProperty(atomicUnit) && !result[groupName]) {
                    result[groupName] = atomicUnit;
                }

                return atomicUnit;
            };

            for (groupName in unitConversions) {
                if (unitConversions.hasOwnProperty(groupName)) {
                    group = unitConversions[groupName];

                    this.map(mapUnit);
                }
            }

            return result;
        };
        Unit.prototype.cancel = function () {
            var counter = {}, atomicUnit, i;

            for (i = 0; i < this.numerator.length; i++) {
                atomicUnit = this.numerator[i];
                counter[atomicUnit] = (counter[atomicUnit] || 0) + 1;
            }

            for (i = 0; i < this.denominator.length; i++) {
                atomicUnit = this.denominator[i];
                counter[atomicUnit] = (counter[atomicUnit] || 0) - 1;
            }

            this.numerator = [];
            this.denominator = [];

            for (atomicUnit in counter) {
                if (counter.hasOwnProperty(atomicUnit)) {
                    var count = counter[atomicUnit];

                    if (count > 0) {
                        for (i = 0; i < count; i++) {
                            this.numerator.push(atomicUnit);
                        }
                    } else if (count < 0) {
                        for (i = 0; i < -count; i++) {
                            this.denominator.push(atomicUnit);
                        }
                    }
                }
            }

            this.numerator.sort();
            this.denominator.sort();
        };
        module.exports = Unit;

    },{"../data/unit-conversions":16,"../utils":89,"./node":76}],85:[function(require,module,exports){
        var Node = require('./node');

        var URL = function (val, index, currentFileInfo, isEvald) {
            this.value = val;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.isEvald = isEvald;
        };
        URL.prototype = new Node();
        URL.prototype.type = 'Url';
        URL.prototype.accept = function (visitor) {
            this.value = visitor.visit(this.value);
        };
        URL.prototype.genCSS = function (context, output) {
            output.add('url(');
            this.value.genCSS(context, output);
            output.add(')');
        };
        URL.prototype.eval = function (context) {
            var val = this.value.eval(context),
                rootpath;

            if (!this.isEvald) {
                // Add the rootpath if the URL requires a rewrite
                rootpath = this.fileInfo() && this.fileInfo().rootpath;
                if (typeof rootpath === 'string' &&
                    typeof val.value === 'string' &&
                    context.pathRequiresRewrite(val.value)) {
                    if (!val.quote) {
                        rootpath = escapePath(rootpath);
                    }
                    val.value = context.rewritePath(val.value, rootpath);
                } else {
                    val.value = context.normalizePath(val.value);
                }

                // Add url args if enabled
                if (context.urlArgs) {
                    if (!val.value.match(/^\s*data:/)) {
                        var delimiter = val.value.indexOf('?') === -1 ? '?' : '&';
                        var urlArgs = delimiter + context.urlArgs;
                        if (val.value.indexOf('#') !== -1) {
                            val.value = val.value.replace('#', urlArgs + '#');
                        } else {
                            val.value += urlArgs;
                        }
                    }
                }
            }

            return new URL(val, this.getIndex(), this.fileInfo(), true);
        };

        function escapePath(path) {
            return path.replace(/[\(\)'"\s]/g, function(match) { return '\\' + match; });
        }

        module.exports = URL;

    },{"./node":76}],86:[function(require,module,exports){
        var Node = require('./node');

        var Value = function (value) {
            if (!value) {
                throw new Error('Value requires an array argument');
            }
            if (!Array.isArray(value)) {
                this.value = [ value ];
            }
            else {
                this.value = value;
            }
        };
        Value.prototype = new Node();
        Value.prototype.type = 'Value';
        Value.prototype.accept = function (visitor) {
            if (this.value) {
                this.value = visitor.visitArray(this.value);
            }
        };
        Value.prototype.eval = function (context) {
            if (this.value.length === 1) {
                return this.value[0].eval(context);
            } else {
                return new Value(this.value.map(function (v) {
                    return v.eval(context);
                }));
            }
        };
        Value.prototype.genCSS = function (context, output) {
            var i;
            for (i = 0; i < this.value.length; i++) {
                this.value[i].genCSS(context, output);
                if (i + 1 < this.value.length) {
                    output.add((context && context.compress) ? ',' : ', ');
                }
            }
        };
        module.exports = Value;

    },{"./node":76}],87:[function(require,module,exports){
        var Node = require('./node'),
            Variable = require('./variable'),
            Ruleset = require('./ruleset'),
            DetachedRuleset = require('./detached-ruleset'),
            LessError = require('../less-error');

        var VariableCall = function (variable, index, currentFileInfo) {
            this.variable = variable;
            this._index = index;
            this._fileInfo = currentFileInfo;
            this.allowRoot = true;
        };
        VariableCall.prototype = new Node();
        VariableCall.prototype.type = 'VariableCall';
        VariableCall.prototype.eval = function (context) {
            var rules, detachedRuleset = new Variable(this.variable, this.getIndex(), this.fileInfo()).eval(context),
                error = new LessError({message: 'Could not evaluate variable call ' + this.variable});

            if (!detachedRuleset.ruleset) {
                if (detachedRuleset.rules) {
                    rules = detachedRuleset;
                }
                else if (Array.isArray(detachedRuleset)) {
                    rules = new Ruleset('', detachedRuleset);
                }
                else if (Array.isArray(detachedRuleset.value)) {
                    rules = new Ruleset('', detachedRuleset.value);
                }
                else {
                    throw error;
                }
                detachedRuleset = new DetachedRuleset(rules);
            }
            if (detachedRuleset.ruleset) {
                return detachedRuleset.callEval(context);
            }
            throw error;
        };
        module.exports = VariableCall;

    },{"../less-error":38,"./detached-ruleset":61,"./node":76,"./ruleset":81,"./variable":88}],88:[function(require,module,exports){
        var Node = require('./node'),
            Call = require('./call');

        var Variable = function (name, index, currentFileInfo) {
            this.name = name;
            this._index = index;
            this._fileInfo = currentFileInfo;
        };
        Variable.prototype = new Node();
        Variable.prototype.type = 'Variable';
        Variable.prototype.eval = function (context) {
            var variable, name = this.name;

            if (name.indexOf('@@') === 0) {
                name = '@' + new Variable(name.slice(1), this.getIndex(), this.fileInfo()).eval(context).value;
            }

            if (this.evaluating) {
                throw { type: 'Name',
                    message: 'Recursive variable definition for ' + name,
                    filename: this.fileInfo().filename,
                    index: this.getIndex() };
            }

            this.evaluating = true;

            variable = this.find(context.frames, function (frame) {
                var v = frame.variable(name);
                if (v) {
                    if (v.important) {
                        var importantScope = context.importantScope[context.importantScope.length - 1];
                        importantScope.important = v.important;
                    }
                    // If in calc, wrap vars in a function call to cascade evaluate args first
                    if (context.inCalc) {
                        return (new Call('_SELF', [v.value])).eval(context);
                    }
                    else {
                        return v.value.eval(context);
                    }
                }
            });
            if (variable) {
                this.evaluating = false;
                return variable;
            } else {
                throw { type: 'Name',
                    message: 'variable ' + name + ' is undefined',
                    filename: this.fileInfo().filename,
                    index: this.getIndex() };
            }
        };
        Variable.prototype.find = function (obj, fun) {
            for (var i = 0, r; i < obj.length; i++) {
                r = fun.call(obj, obj[i]);
                if (r) { return r; }
            }
            return null;
        };
        module.exports = Variable;

    },{"./call":54,"./node":76}],89:[function(require,module,exports){
        /* jshint proto: true */
        var Constants = require('./constants');
        var clone = require('clone');

        var utils = {
            getLocation: function(index, inputStream) {
                var n = index + 1,
                    line = null,
                    column = -1;

                while (--n >= 0 && inputStream.charAt(n) !== '\n') {
                    column++;
                }

                if (typeof index === 'number') {
                    line = (inputStream.slice(0, index).match(/\n/g) || '').length;
                }

                return {
                    line: line,
                    column: column
                };
            },
            copyArray: function(arr) {
                var i, length = arr.length,
                    copy = new Array(length);

                for (i = 0; i < length; i++) {
                    copy[i] = arr[i];
                }
                return copy;
            },
            clone: function (obj) {
                var cloned = {};
                for (var prop in obj) {
                    if (obj.hasOwnProperty(prop)) {
                        cloned[prop] = obj[prop];
                    }
                }
                return cloned;
            },
            copyOptions: function(obj1, obj2) {
                if (obj2 && obj2._defaults) {
                    return obj2;
                }
                var opts = utils.defaults(obj1, obj2);
                if (opts.strictMath) {
                    opts.math = Constants.Math.STRICT_LEGACY;
                }
                // Back compat with changed relativeUrls option
                if (opts.relativeUrls) {
                    opts.rewriteUrls = Constants.RewriteUrls.ALL;
                }
                if (typeof opts.math === 'string') {
                    switch (opts.math.toLowerCase()) {
                        case 'always':
                            opts.math = Constants.Math.ALWAYS;
                            break;
                        case 'parens-division':
                            opts.math = Constants.Math.PARENS_DIVISION;
                            break;
                        case 'strict':
                        case 'parens':
                            opts.math = Constants.Math.PARENS;
                            break;
                        case 'strict-legacy':
                            opts.math = Constants.Math.STRICT_LEGACY;
                    }
                }
                if (typeof opts.rewriteUrls === 'string') {
                    switch (opts.rewriteUrls.toLowerCase()) {
                        case 'off':
                            opts.rewriteUrls = Constants.RewriteUrls.OFF;
                            break;
                        case 'local':
                            opts.rewriteUrls = Constants.RewriteUrls.LOCAL;
                            break;
                        case 'all':
                            opts.rewriteUrls = Constants.RewriteUrls.ALL;
                            break;
                    }
                }
                return opts;
            },
            defaults: function(obj1, obj2) {
                var newObj = obj2 || {};
                if (!obj2._defaults) {
                    newObj = {};
                    var defaults = clone(obj1);
                    newObj._defaults = defaults;
                    var cloned = obj2 ? clone(obj2) : {};
                    Object.assign(newObj, defaults, cloned);
                }
                return newObj;
            },
            merge: function(obj1, obj2) {
                for (var prop in obj2) {
                    if (obj2.hasOwnProperty(prop)) {
                        obj1[prop] = obj2[prop];
                    }
                }
                return obj1;
            },
            flattenArray: function(arr, result) {
                result = result || [];
                for (var i = 0, length = arr.length; i < length; i++) {
                    var value = arr[i];
                    if (Array.isArray(value)) {
                        utils.flattenArray(value, result);
                    } else {
                        if (value !== undefined) {
                            result.push(value);
                        }
                    }
                }
                return result;
            }
        };

        module.exports = utils;
    },{"./constants":12,"clone":100}],90:[function(require,module,exports){
        var tree = require('../tree'),
            Visitor = require('./visitor'),
            logger = require('../logger'),
            utils = require('../utils');

        /* jshint loopfunc:true */

        var ExtendFinderVisitor = function() {
            this._visitor = new Visitor(this);
            this.contexts = [];
            this.allExtendsStack = [[]];
        };

        ExtendFinderVisitor.prototype = {
            run: function (root) {
                root = this._visitor.visit(root);
                root.allExtends = this.allExtendsStack[0];
                return root;
            },
            visitDeclaration: function (declNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },
            visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },
            visitRuleset: function (rulesetNode, visitArgs) {
                if (rulesetNode.root) {
                    return;
                }

                var i, j, extend, allSelectorsExtendList = [], extendList;

                // get &:extend(.a); rules which apply to all selectors in this ruleset
                var rules = rulesetNode.rules, ruleCnt = rules ? rules.length : 0;
                for (i = 0; i < ruleCnt; i++) {
                    if (rulesetNode.rules[i] instanceof tree.Extend) {
                        allSelectorsExtendList.push(rules[i]);
                        rulesetNode.extendOnEveryPath = true;
                    }
                }

                // now find every selector and apply the extends that apply to all extends
                // and the ones which apply to an individual extend
                var paths = rulesetNode.paths;
                for (i = 0; i < paths.length; i++) {
                    var selectorPath = paths[i],
                        selector = selectorPath[selectorPath.length - 1],
                        selExtendList = selector.extendList;

                    extendList = selExtendList ? utils.copyArray(selExtendList).concat(allSelectorsExtendList)
                        : allSelectorsExtendList;

                    if (extendList) {
                        extendList = extendList.map(function(allSelectorsExtend) {
                            return allSelectorsExtend.clone();
                        });
                    }

                    for (j = 0; j < extendList.length; j++) {
                        this.foundExtends = true;
                        extend = extendList[j];
                        extend.findSelfSelectors(selectorPath);
                        extend.ruleset = rulesetNode;
                        if (j === 0) { extend.firstExtendOnThisSelectorPath = true; }
                        this.allExtendsStack[this.allExtendsStack.length - 1].push(extend);
                    }
                }

                this.contexts.push(rulesetNode.selectors);
            },
            visitRulesetOut: function (rulesetNode) {
                if (!rulesetNode.root) {
                    this.contexts.length = this.contexts.length - 1;
                }
            },
            visitMedia: function (mediaNode, visitArgs) {
                mediaNode.allExtends = [];
                this.allExtendsStack.push(mediaNode.allExtends);
            },
            visitMediaOut: function (mediaNode) {
                this.allExtendsStack.length = this.allExtendsStack.length - 1;
            },
            visitAtRule: function (atRuleNode, visitArgs) {
                atRuleNode.allExtends = [];
                this.allExtendsStack.push(atRuleNode.allExtends);
            },
            visitAtRuleOut: function (atRuleNode) {
                this.allExtendsStack.length = this.allExtendsStack.length - 1;
            }
        };

        var ProcessExtendsVisitor = function() {
            this._visitor = new Visitor(this);
        };

        ProcessExtendsVisitor.prototype = {
            run: function(root) {
                var extendFinder = new ExtendFinderVisitor();
                this.extendIndices = {};
                extendFinder.run(root);
                if (!extendFinder.foundExtends) { return root; }
                root.allExtends = root.allExtends.concat(this.doExtendChaining(root.allExtends, root.allExtends));
                this.allExtendsStack = [root.allExtends];
                var newRoot = this._visitor.visit(root);
                this.checkExtendsForNonMatched(root.allExtends);
                return newRoot;
            },
            checkExtendsForNonMatched: function(extendList) {
                var indices = this.extendIndices;
                extendList.filter(function(extend) {
                    return !extend.hasFoundMatches && extend.parent_ids.length == 1;
                }).forEach(function(extend) {
                    var selector = '_unknown_';
                    try {
                        selector = extend.selector.toCSS({});
                    }
                    catch (_) {}

                    if (!indices[extend.index + ' ' + selector]) {
                        indices[extend.index + ' ' + selector] = true;
                        logger.warn('extend \'' + selector + '\' has no matches');
                    }
                });
            },
            doExtendChaining: function (extendsList, extendsListTarget, iterationCount) {
                //
                // chaining is different from normal extension.. if we extend an extend then we are not just copying, altering
                // and pasting the selector we would do normally, but we are also adding an extend with the same target selector
                // this means this new extend can then go and alter other extends
                //
                // this method deals with all the chaining work - without it, extend is flat and doesn't work on other extend selectors
                // this is also the most expensive.. and a match on one selector can cause an extension of a selector we had already
                // processed if we look at each selector at a time, as is done in visitRuleset

                var extendIndex, targetExtendIndex, matches, extendsToAdd = [], newSelector, extendVisitor = this, selectorPath,
                    extend, targetExtend, newExtend;

                iterationCount = iterationCount || 0;

                // loop through comparing every extend with every target extend.
                // a target extend is the one on the ruleset we are looking at copy/edit/pasting in place
                // e.g.  .a:extend(.b) {}  and .b:extend(.c) {} then the first extend extends the second one
                // and the second is the target.
                // the separation into two lists allows us to process a subset of chains with a bigger set, as is the
                // case when processing media queries
                for (extendIndex = 0; extendIndex < extendsList.length; extendIndex++) {
                    for (targetExtendIndex = 0; targetExtendIndex < extendsListTarget.length; targetExtendIndex++) {

                        extend = extendsList[extendIndex];
                        targetExtend = extendsListTarget[targetExtendIndex];

                        // look for circular references
                        if ( extend.parent_ids.indexOf( targetExtend.object_id ) >= 0 ) { continue; }

                        // find a match in the target extends self selector (the bit before :extend)
                        selectorPath = [targetExtend.selfSelectors[0]];
                        matches = extendVisitor.findMatch(extend, selectorPath);

                        if (matches.length) {
                            extend.hasFoundMatches = true;

                            // we found a match, so for each self selector..
                            extend.selfSelectors.forEach(function(selfSelector) {
                                var info = targetExtend.visibilityInfo();

                                // process the extend as usual
                                newSelector = extendVisitor.extendSelector(matches, selectorPath, selfSelector, extend.isVisible());

                                // but now we create a new extend from it
                                newExtend = new(tree.Extend)(targetExtend.selector, targetExtend.option, 0, targetExtend.fileInfo(), info);
                                newExtend.selfSelectors = newSelector;

                                // add the extend onto the list of extends for that selector
                                newSelector[newSelector.length - 1].extendList = [newExtend];

                                // record that we need to add it.
                                extendsToAdd.push(newExtend);
                                newExtend.ruleset = targetExtend.ruleset;

                                // remember its parents for circular references
                                newExtend.parent_ids = newExtend.parent_ids.concat(targetExtend.parent_ids, extend.parent_ids);

                                // only process the selector once.. if we have :extend(.a,.b) then multiple
                                // extends will look at the same selector path, so when extending
                                // we know that any others will be duplicates in terms of what is added to the css
                                if (targetExtend.firstExtendOnThisSelectorPath) {
                                    newExtend.firstExtendOnThisSelectorPath = true;
                                    targetExtend.ruleset.paths.push(newSelector);
                                }
                            });
                        }
                    }
                }

                if (extendsToAdd.length) {
                    // try to detect circular references to stop a stack overflow.
                    // may no longer be needed.
                    this.extendChainCount++;
                    if (iterationCount > 100) {
                        var selectorOne = '{unable to calculate}';
                        var selectorTwo = '{unable to calculate}';
                        try {
                            selectorOne = extendsToAdd[0].selfSelectors[0].toCSS();
                            selectorTwo = extendsToAdd[0].selector.toCSS();
                        }
                        catch (e) {}
                        throw { message: 'extend circular reference detected. One of the circular extends is currently:' +
                                selectorOne + ':extend(' + selectorTwo + ')'};
                    }

                    // now process the new extends on the existing rules so that we can handle a extending b extending c extending
                    // d extending e...
                    return extendsToAdd.concat(extendVisitor.doExtendChaining(extendsToAdd, extendsListTarget, iterationCount + 1));
                } else {
                    return extendsToAdd;
                }
            },
            visitDeclaration: function (ruleNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },
            visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },
            visitSelector: function (selectorNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },
            visitRuleset: function (rulesetNode, visitArgs) {
                if (rulesetNode.root) {
                    return;
                }
                var matches, pathIndex, extendIndex, allExtends = this.allExtendsStack[this.allExtendsStack.length - 1],
                    selectorsToAdd = [], extendVisitor = this, selectorPath;

                // look at each selector path in the ruleset, find any extend matches and then copy, find and replace

                for (extendIndex = 0; extendIndex < allExtends.length; extendIndex++) {
                    for (pathIndex = 0; pathIndex < rulesetNode.paths.length; pathIndex++) {
                        selectorPath = rulesetNode.paths[pathIndex];

                        // extending extends happens initially, before the main pass
                        if (rulesetNode.extendOnEveryPath) { continue; }
                        var extendList = selectorPath[selectorPath.length - 1].extendList;
                        if (extendList && extendList.length) { continue; }

                        matches = this.findMatch(allExtends[extendIndex], selectorPath);

                        if (matches.length) {
                            allExtends[extendIndex].hasFoundMatches = true;

                            allExtends[extendIndex].selfSelectors.forEach(function(selfSelector) {
                                var extendedSelectors;
                                extendedSelectors = extendVisitor.extendSelector(matches, selectorPath, selfSelector, allExtends[extendIndex].isVisible());
                                selectorsToAdd.push(extendedSelectors);
                            });
                        }
                    }
                }
                rulesetNode.paths = rulesetNode.paths.concat(selectorsToAdd);
            },
            findMatch: function (extend, haystackSelectorPath) {
                //
                // look through the haystack selector path to try and find the needle - extend.selector
                // returns an array of selector matches that can then be replaced
                //
                var haystackSelectorIndex, hackstackSelector, hackstackElementIndex, haystackElement,
                    targetCombinator, i,
                    extendVisitor = this,
                    needleElements = extend.selector.elements,
                    potentialMatches = [], potentialMatch, matches = [];

                // loop through the haystack elements
                for (haystackSelectorIndex = 0; haystackSelectorIndex < haystackSelectorPath.length; haystackSelectorIndex++) {
                    hackstackSelector = haystackSelectorPath[haystackSelectorIndex];

                    for (hackstackElementIndex = 0; hackstackElementIndex < hackstackSelector.elements.length; hackstackElementIndex++) {

                        haystackElement = hackstackSelector.elements[hackstackElementIndex];

                        // if we allow elements before our match we can add a potential match every time. otherwise only at the first element.
                        if (extend.allowBefore || (haystackSelectorIndex === 0 && hackstackElementIndex === 0)) {
                            potentialMatches.push({pathIndex: haystackSelectorIndex, index: hackstackElementIndex, matched: 0,
                                initialCombinator: haystackElement.combinator});
                        }

                        for (i = 0; i < potentialMatches.length; i++) {
                            potentialMatch = potentialMatches[i];

                            // selectors add " " onto the first element. When we use & it joins the selectors together, but if we don't
                            // then each selector in haystackSelectorPath has a space before it added in the toCSS phase. so we need to
                            // work out what the resulting combinator will be
                            targetCombinator = haystackElement.combinator.value;
                            if (targetCombinator === '' && hackstackElementIndex === 0) {
                                targetCombinator = ' ';
                            }

                            // if we don't match, null our match to indicate failure
                            if (!extendVisitor.isElementValuesEqual(needleElements[potentialMatch.matched].value, haystackElement.value) ||
                                (potentialMatch.matched > 0 && needleElements[potentialMatch.matched].combinator.value !== targetCombinator)) {
                                potentialMatch = null;
                            } else {
                                potentialMatch.matched++;
                            }

                            // if we are still valid and have finished, test whether we have elements after and whether these are allowed
                            if (potentialMatch) {
                                potentialMatch.finished = potentialMatch.matched === needleElements.length;
                                if (potentialMatch.finished &&
                                    (!extend.allowAfter &&
                                        (hackstackElementIndex + 1 < hackstackSelector.elements.length || haystackSelectorIndex + 1 < haystackSelectorPath.length))) {
                                    potentialMatch = null;
                                }
                            }
                            // if null we remove, if not, we are still valid, so either push as a valid match or continue
                            if (potentialMatch) {
                                if (potentialMatch.finished) {
                                    potentialMatch.length = needleElements.length;
                                    potentialMatch.endPathIndex = haystackSelectorIndex;
                                    potentialMatch.endPathElementIndex = hackstackElementIndex + 1; // index after end of match
                                    potentialMatches.length = 0; // we don't allow matches to overlap, so start matching again
                                    matches.push(potentialMatch);
                                }
                            } else {
                                potentialMatches.splice(i, 1);
                                i--;
                            }
                        }
                    }
                }
                return matches;
            },
            isElementValuesEqual: function(elementValue1, elementValue2) {
                if (typeof elementValue1 === 'string' || typeof elementValue2 === 'string') {
                    return elementValue1 === elementValue2;
                }
                if (elementValue1 instanceof tree.Attribute) {
                    if (elementValue1.op !== elementValue2.op || elementValue1.key !== elementValue2.key) {
                        return false;
                    }
                    if (!elementValue1.value || !elementValue2.value) {
                        if (elementValue1.value || elementValue2.value) {
                            return false;
                        }
                        return true;
                    }
                    elementValue1 = elementValue1.value.value || elementValue1.value;
                    elementValue2 = elementValue2.value.value || elementValue2.value;
                    return elementValue1 === elementValue2;
                }
                elementValue1 = elementValue1.value;
                elementValue2 = elementValue2.value;
                if (elementValue1 instanceof tree.Selector) {
                    if (!(elementValue2 instanceof tree.Selector) || elementValue1.elements.length !== elementValue2.elements.length) {
                        return false;
                    }
                    for (var i = 0; i  < elementValue1.elements.length; i++) {
                        if (elementValue1.elements[i].combinator.value !== elementValue2.elements[i].combinator.value) {
                            if (i !== 0 || (elementValue1.elements[i].combinator.value || ' ') !== (elementValue2.elements[i].combinator.value || ' ')) {
                                return false;
                            }
                        }
                        if (!this.isElementValuesEqual(elementValue1.elements[i].value, elementValue2.elements[i].value)) {
                            return false;
                        }
                    }
                    return true;
                }
                return false;
            },
            extendSelector:function (matches, selectorPath, replacementSelector, isVisible) {

                // for a set of matches, replace each match with the replacement selector

                var currentSelectorPathIndex = 0,
                    currentSelectorPathElementIndex = 0,
                    path = [],
                    matchIndex,
                    selector,
                    firstElement,
                    match,
                    newElements;

                for (matchIndex = 0; matchIndex < matches.length; matchIndex++) {
                    match = matches[matchIndex];
                    selector = selectorPath[match.pathIndex];
                    firstElement = new tree.Element(
                        match.initialCombinator,
                        replacementSelector.elements[0].value,
                        replacementSelector.elements[0].isVariable,
                        replacementSelector.elements[0].getIndex(),
                        replacementSelector.elements[0].fileInfo()
                    );

                    if (match.pathIndex > currentSelectorPathIndex && currentSelectorPathElementIndex > 0) {
                        path[path.length - 1].elements = path[path.length - 1]
                            .elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
                        currentSelectorPathElementIndex = 0;
                        currentSelectorPathIndex++;
                    }

                    newElements = selector.elements
                        .slice(currentSelectorPathElementIndex, match.index)
                        .concat([firstElement])
                        .concat(replacementSelector.elements.slice(1));

                    if (currentSelectorPathIndex === match.pathIndex && matchIndex > 0) {
                        path[path.length - 1].elements =
                            path[path.length - 1].elements.concat(newElements);
                    } else {
                        path = path.concat(selectorPath.slice(currentSelectorPathIndex, match.pathIndex));

                        path.push(new tree.Selector(
                            newElements
                        ));
                    }
                    currentSelectorPathIndex = match.endPathIndex;
                    currentSelectorPathElementIndex = match.endPathElementIndex;
                    if (currentSelectorPathElementIndex >= selectorPath[currentSelectorPathIndex].elements.length) {
                        currentSelectorPathElementIndex = 0;
                        currentSelectorPathIndex++;
                    }
                }

                if (currentSelectorPathIndex < selectorPath.length && currentSelectorPathElementIndex > 0) {
                    path[path.length - 1].elements = path[path.length - 1]
                        .elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
                    currentSelectorPathIndex++;
                }

                path = path.concat(selectorPath.slice(currentSelectorPathIndex, selectorPath.length));
                path = path.map(function (currentValue) {
                    // we can re-use elements here, because the visibility property matters only for selectors
                    var derived = currentValue.createDerived(currentValue.elements);
                    if (isVisible) {
                        derived.ensureVisibility();
                    } else {
                        derived.ensureInvisibility();
                    }
                    return derived;
                });
                return path;
            },
            visitMedia: function (mediaNode, visitArgs) {
                var newAllExtends = mediaNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length - 1]);
                newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, mediaNode.allExtends));
                this.allExtendsStack.push(newAllExtends);
            },
            visitMediaOut: function (mediaNode) {
                var lastIndex = this.allExtendsStack.length - 1;
                this.allExtendsStack.length = lastIndex;
            },
            visitAtRule: function (atRuleNode, visitArgs) {
                var newAllExtends = atRuleNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length - 1]);
                newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, atRuleNode.allExtends));
                this.allExtendsStack.push(newAllExtends);
            },
            visitAtRuleOut: function (atRuleNode) {
                var lastIndex = this.allExtendsStack.length - 1;
                this.allExtendsStack.length = lastIndex;
            }
        };

        module.exports = ProcessExtendsVisitor;

    },{"../logger":39,"../tree":67,"../utils":89,"./visitor":97}],91:[function(require,module,exports){
        function ImportSequencer(onSequencerEmpty) {
            this.imports = [];
            this.variableImports = [];
            this._onSequencerEmpty = onSequencerEmpty;
            this._currentDepth = 0;
        }

        ImportSequencer.prototype.addImport = function(callback) {
            var importSequencer = this,
                importItem = {
                    callback: callback,
                    args: null,
                    isReady: false
                };
            this.imports.push(importItem);
            return function() {
                importItem.args = Array.prototype.slice.call(arguments, 0);
                importItem.isReady = true;
                importSequencer.tryRun();
            };
        };

        ImportSequencer.prototype.addVariableImport = function(callback) {
            this.variableImports.push(callback);
        };

        ImportSequencer.prototype.tryRun = function() {
            this._currentDepth++;
            try {
                while (true) {
                    while (this.imports.length > 0) {
                        var importItem = this.imports[0];
                        if (!importItem.isReady) {
                            return;
                        }
                        this.imports = this.imports.slice(1);
                        importItem.callback.apply(null, importItem.args);
                    }
                    if (this.variableImports.length === 0) {
                        break;
                    }
                    var variableImport = this.variableImports[0];
                    this.variableImports = this.variableImports.slice(1);
                    variableImport();
                }
            } finally {
                this._currentDepth--;
            }
            if (this._currentDepth === 0 && this._onSequencerEmpty) {
                this._onSequencerEmpty();
            }
        };

        module.exports = ImportSequencer;

    },{}],92:[function(require,module,exports){
        var contexts = require('../contexts'),
            Visitor = require('./visitor'),
            ImportSequencer = require('./import-sequencer'),
            utils = require('../utils');

        var ImportVisitor = function(importer, finish) {

            this._visitor = new Visitor(this);
            this._importer = importer;
            this._finish = finish;
            this.context = new contexts.Eval();
            this.importCount = 0;
            this.onceFileDetectionMap = {};
            this.recursionDetector = {};
            this._sequencer = new ImportSequencer(this._onSequencerEmpty.bind(this));
        };

        ImportVisitor.prototype = {
            isReplacing: false,
            run: function (root) {
                try {
                    // process the contents
                    this._visitor.visit(root);
                }
                catch (e) {
                    this.error = e;
                }

                this.isFinished = true;
                this._sequencer.tryRun();
            },
            _onSequencerEmpty: function() {
                if (!this.isFinished) {
                    return;
                }
                this._finish(this.error);
            },
            visitImport: function (importNode, visitArgs) {
                var inlineCSS = importNode.options.inline;

                if (!importNode.css || inlineCSS) {

                    var context = new contexts.Eval(this.context, utils.copyArray(this.context.frames));
                    var importParent = context.frames[0];

                    this.importCount++;
                    if (importNode.isVariableImport()) {
                        this._sequencer.addVariableImport(this.processImportNode.bind(this, importNode, context, importParent));
                    } else {
                        this.processImportNode(importNode, context, importParent);
                    }
                }
                visitArgs.visitDeeper = false;
            },
            processImportNode: function(importNode, context, importParent) {
                var evaldImportNode,
                    inlineCSS = importNode.options.inline;

                try {
                    evaldImportNode = importNode.evalForImport(context);
                } catch (e) {
                    if (!e.filename) { e.index = importNode.getIndex(); e.filename = importNode.fileInfo().filename; }
                    // attempt to eval properly and treat as css
                    importNode.css = true;
                    // if that fails, this error will be thrown
                    importNode.error = e;
                }

                if (evaldImportNode && (!evaldImportNode.css || inlineCSS)) {

                    if (evaldImportNode.options.multiple) {
                        context.importMultiple = true;
                    }

                    // try appending if we haven't determined if it is css or not
                    var tryAppendLessExtension = evaldImportNode.css === undefined;

                    for (var i = 0; i < importParent.rules.length; i++) {
                        if (importParent.rules[i] === importNode) {
                            importParent.rules[i] = evaldImportNode;
                            break;
                        }
                    }

                    var onImported = this.onImported.bind(this, evaldImportNode, context),
                        sequencedOnImported = this._sequencer.addImport(onImported);

                    this._importer.push(evaldImportNode.getPath(), tryAppendLessExtension, evaldImportNode.fileInfo(),
                        evaldImportNode.options, sequencedOnImported);
                } else {
                    this.importCount--;
                    if (this.isFinished) {
                        this._sequencer.tryRun();
                    }
                }
            },
            onImported: function (importNode, context, e, root, importedAtRoot, fullPath) {
                if (e) {
                    if (!e.filename) {
                        e.index = importNode.getIndex(); e.filename = importNode.fileInfo().filename;
                    }
                    this.error = e;
                }

                var importVisitor = this,
                    inlineCSS = importNode.options.inline,
                    isPlugin = importNode.options.isPlugin,
                    isOptional = importNode.options.optional,
                    duplicateImport = importedAtRoot || fullPath in importVisitor.recursionDetector;

                if (!context.importMultiple) {
                    if (duplicateImport) {
                        importNode.skip = true;
                    } else {
                        importNode.skip = function() {
                            if (fullPath in importVisitor.onceFileDetectionMap) {
                                return true;
                            }
                            importVisitor.onceFileDetectionMap[fullPath] = true;
                            return false;
                        };
                    }
                }

                if (!fullPath && isOptional) {
                    importNode.skip = true;
                }

                if (root) {
                    importNode.root = root;
                    importNode.importedFilename = fullPath;

                    if (!inlineCSS && !isPlugin && (context.importMultiple || !duplicateImport)) {
                        importVisitor.recursionDetector[fullPath] = true;

                        var oldContext = this.context;
                        this.context = context;
                        try {
                            this._visitor.visit(root);
                        } catch (e) {
                            this.error = e;
                        }
                        this.context = oldContext;
                    }
                }

                importVisitor.importCount--;

                if (importVisitor.isFinished) {
                    importVisitor._sequencer.tryRun();
                }
            },
            visitDeclaration: function (declNode, visitArgs) {
                if (declNode.value.type === 'DetachedRuleset') {
                    this.context.frames.unshift(declNode);
                } else {
                    visitArgs.visitDeeper = false;
                }
            },
            visitDeclarationOut: function(declNode) {
                if (declNode.value.type === 'DetachedRuleset') {
                    this.context.frames.shift();
                }
            },
            visitAtRule: function (atRuleNode, visitArgs) {
                this.context.frames.unshift(atRuleNode);
            },
            visitAtRuleOut: function (atRuleNode) {
                this.context.frames.shift();
            },
            visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
                this.context.frames.unshift(mixinDefinitionNode);
            },
            visitMixinDefinitionOut: function (mixinDefinitionNode) {
                this.context.frames.shift();
            },
            visitRuleset: function (rulesetNode, visitArgs) {
                this.context.frames.unshift(rulesetNode);
            },
            visitRulesetOut: function (rulesetNode) {
                this.context.frames.shift();
            },
            visitMedia: function (mediaNode, visitArgs) {
                this.context.frames.unshift(mediaNode.rules[0]);
            },
            visitMediaOut: function (mediaNode) {
                this.context.frames.shift();
            }
        };
        module.exports = ImportVisitor;

    },{"../contexts":13,"../utils":89,"./import-sequencer":91,"./visitor":97}],93:[function(require,module,exports){
        var visitors = {
            Visitor: require('./visitor'),
            ImportVisitor: require('./import-visitor'),
            MarkVisibleSelectorsVisitor: require('./set-tree-visibility-visitor'),
            ExtendVisitor: require('./extend-visitor'),
            JoinSelectorVisitor: require('./join-selector-visitor'),
            ToCSSVisitor: require('./to-css-visitor')
        };

        module.exports = visitors;

    },{"./extend-visitor":90,"./import-visitor":92,"./join-selector-visitor":94,"./set-tree-visibility-visitor":95,"./to-css-visitor":96,"./visitor":97}],94:[function(require,module,exports){
        var Visitor = require('./visitor');

        var JoinSelectorVisitor = function() {
            this.contexts = [[]];
            this._visitor = new Visitor(this);
        };

        JoinSelectorVisitor.prototype = {
            run: function (root) {
                return this._visitor.visit(root);
            },
            visitDeclaration: function (declNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },
            visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
                visitArgs.visitDeeper = false;
            },

            visitRuleset: function (rulesetNode, visitArgs) {
                var context = this.contexts[this.contexts.length - 1],
                    paths = [], selectors;

                this.contexts.push(paths);

                if (!rulesetNode.root) {
                    selectors = rulesetNode.selectors;
                    if (selectors) {
                        selectors = selectors.filter(function(selector) { return selector.getIsOutput(); });
                        rulesetNode.selectors = selectors.length ? selectors : (selectors = null);
                        if (selectors) { rulesetNode.joinSelectors(paths, context, selectors); }
                    }
                    if (!selectors) { rulesetNode.rules = null; }
                    rulesetNode.paths = paths;
                }
            },
            visitRulesetOut: function (rulesetNode) {
                this.contexts.length = this.contexts.length - 1;
            },
            visitMedia: function (mediaNode, visitArgs) {
                var context = this.contexts[this.contexts.length - 1];
                mediaNode.rules[0].root = (context.length === 0 || context[0].multiMedia);
            },
            visitAtRule: function (atRuleNode, visitArgs) {
                var context = this.contexts[this.contexts.length - 1];
                if (atRuleNode.rules && atRuleNode.rules.length) {
                    atRuleNode.rules[0].root = (atRuleNode.isRooted || context.length === 0 || null);
                }
            }
        };

        module.exports = JoinSelectorVisitor;

    },{"./visitor":97}],95:[function(require,module,exports){
        var SetTreeVisibilityVisitor = function(visible) {
            this.visible = visible;
        };
        SetTreeVisibilityVisitor.prototype.run = function(root) {
            this.visit(root);
        };
        SetTreeVisibilityVisitor.prototype.visitArray = function(nodes) {
            if (!nodes) {
                return nodes;
            }

            var cnt = nodes.length, i;
            for (i = 0; i < cnt; i++) {
                this.visit(nodes[i]);
            }
            return nodes;
        };
        SetTreeVisibilityVisitor.prototype.visit = function(node) {
            if (!node) {
                return node;
            }
            if (node.constructor === Array) {
                return this.visitArray(node);
            }

            if (!node.blocksVisibility || node.blocksVisibility()) {
                return node;
            }
            if (this.visible) {
                node.ensureVisibility();
            } else {
                node.ensureInvisibility();
            }

            node.accept(this);
            return node;
        };
        module.exports = SetTreeVisibilityVisitor;
    },{}],96:[function(require,module,exports){
        var tree = require('../tree'),
            Visitor = require('./visitor');

        var CSSVisitorUtils = function(context) {
            this._visitor = new Visitor(this);
            this._context = context;
        };

        CSSVisitorUtils.prototype = {
            containsSilentNonBlockedChild: function(bodyRules) {
                var rule;
                if (!bodyRules) {
                    return false;
                }
                for (var r = 0; r < bodyRules.length; r++) {
                    rule = bodyRules[r];
                    if (rule.isSilent && rule.isSilent(this._context) && !rule.blocksVisibility()) {
                        // the atrule contains something that was referenced (likely by extend)
                        // therefore it needs to be shown in output too
                        return true;
                    }
                }
                return false;
            },

            keepOnlyVisibleChilds: function(owner) {
                if (owner && owner.rules) {
                    owner.rules = owner.rules.filter(function(thing) {
                        return thing.isVisible();
                    });
                }
            },

            isEmpty: function(owner) {
                return (owner && owner.rules)
                    ? (owner.rules.length === 0) : true;
            },

            hasVisibleSelector: function(rulesetNode) {
                return (rulesetNode && rulesetNode.paths)
                    ? (rulesetNode.paths.length > 0) : false;
            },

            resolveVisibility: function (node, originalRules) {
                if (!node.blocksVisibility()) {
                    if (this.isEmpty(node) && !this.containsSilentNonBlockedChild(originalRules)) {
                        return ;
                    }

                    return node;
                }

                var compiledRulesBody = node.rules[0];
                this.keepOnlyVisibleChilds(compiledRulesBody);

                if (this.isEmpty(compiledRulesBody)) {
                    return ;
                }

                node.ensureVisibility();
                node.removeVisibilityBlock();

                return node;
            },

            isVisibleRuleset: function(rulesetNode) {
                if (rulesetNode.firstRoot) {
                    return true;
                }

                if (this.isEmpty(rulesetNode)) {
                    return false;
                }

                if (!rulesetNode.root && !this.hasVisibleSelector(rulesetNode)) {
                    return false;
                }

                return true;
            }

        };

        var ToCSSVisitor = function(context) {
            this._visitor = new Visitor(this);
            this._context = context;
            this.utils = new CSSVisitorUtils(context);
        };

        ToCSSVisitor.prototype = {
            isReplacing: true,
            run: function (root) {
                return this._visitor.visit(root);
            },

            visitDeclaration: function (declNode, visitArgs) {
                if (declNode.blocksVisibility() || declNode.variable) {
                    return;
                }
                return declNode;
            },

            visitMixinDefinition: function (mixinNode, visitArgs) {
                // mixin definitions do not get eval'd - this means they keep state
                // so we have to clear that state here so it isn't used if toCSS is called twice
                mixinNode.frames = [];
            },

            visitExtend: function (extendNode, visitArgs) {
            },

            visitComment: function (commentNode, visitArgs) {
                if (commentNode.blocksVisibility() || commentNode.isSilent(this._context)) {
                    return;
                }
                return commentNode;
            },

            visitMedia: function(mediaNode, visitArgs) {
                var originalRules = mediaNode.rules[0].rules;
                mediaNode.accept(this._visitor);
                visitArgs.visitDeeper = false;

                return this.utils.resolveVisibility(mediaNode, originalRules);
            },

            visitImport: function (importNode, visitArgs) {
                if (importNode.blocksVisibility()) {
                    return ;
                }
                return importNode;
            },

            visitAtRule: function(atRuleNode, visitArgs) {
                if (atRuleNode.rules && atRuleNode.rules.length) {
                    return this.visitAtRuleWithBody(atRuleNode, visitArgs);
                } else {
                    return this.visitAtRuleWithoutBody(atRuleNode, visitArgs);
                }
            },

            visitAnonymous: function(anonymousNode, visitArgs) {
                if (!anonymousNode.blocksVisibility()) {
                    anonymousNode.accept(this._visitor);
                    return anonymousNode;
                }
            },

            visitAtRuleWithBody: function(atRuleNode, visitArgs) {
                // if there is only one nested ruleset and that one has no path, then it is
                // just fake ruleset
                function hasFakeRuleset(atRuleNode) {
                    var bodyRules = atRuleNode.rules;
                    return bodyRules.length === 1 && (!bodyRules[0].paths || bodyRules[0].paths.length === 0);
                }
                function getBodyRules(atRuleNode) {
                    var nodeRules = atRuleNode.rules;
                    if (hasFakeRuleset(atRuleNode)) {
                        return nodeRules[0].rules;
                    }

                    return nodeRules;
                }
                // it is still true that it is only one ruleset in array
                // this is last such moment
                // process childs
                var originalRules = getBodyRules(atRuleNode);
                atRuleNode.accept(this._visitor);
                visitArgs.visitDeeper = false;

                if (!this.utils.isEmpty(atRuleNode)) {
                    this._mergeRules(atRuleNode.rules[0].rules);
                }

                return this.utils.resolveVisibility(atRuleNode, originalRules);
            },

            visitAtRuleWithoutBody: function(atRuleNode, visitArgs) {
                if (atRuleNode.blocksVisibility()) {
                    return;
                }

                if (atRuleNode.name === '@charset') {
                    // Only output the debug info together with subsequent @charset definitions
                    // a comment (or @media statement) before the actual @charset atrule would
                    // be considered illegal css as it has to be on the first line
                    if (this.charset) {
                        if (atRuleNode.debugInfo) {
                            var comment = new tree.Comment('/* ' + atRuleNode.toCSS(this._context).replace(/\n/g, '') + ' */\n');
                            comment.debugInfo = atRuleNode.debugInfo;
                            return this._visitor.visit(comment);
                        }
                        return;
                    }
                    this.charset = true;
                }

                return atRuleNode;
            },

            checkValidNodes: function(rules, isRoot) {
                if (!rules) {
                    return;
                }

                for (var i = 0; i < rules.length; i++) {
                    var ruleNode = rules[i];
                    if (isRoot && ruleNode instanceof tree.Declaration && !ruleNode.variable) {
                        throw { message: 'Properties must be inside selector blocks. They cannot be in the root',
                            index: ruleNode.getIndex(), filename: ruleNode.fileInfo() && ruleNode.fileInfo().filename};
                    }
                    if (ruleNode instanceof tree.Call) {
                        throw { message: 'Function \'' + ruleNode.name + '\' is undefined',
                            index: ruleNode.getIndex(), filename: ruleNode.fileInfo() && ruleNode.fileInfo().filename};
                    }
                    if (ruleNode.type && !ruleNode.allowRoot) {
                        throw { message: ruleNode.type + ' node returned by a function is not valid here',
                            index: ruleNode.getIndex(), filename: ruleNode.fileInfo() && ruleNode.fileInfo().filename};
                    }
                }
            },

            visitRuleset: function (rulesetNode, visitArgs) {
                // at this point rulesets are nested into each other
                var rule, rulesets = [];

                this.checkValidNodes(rulesetNode.rules, rulesetNode.firstRoot);

                if (!rulesetNode.root) {
                    // remove invisible paths
                    this._compileRulesetPaths(rulesetNode);

                    // remove rulesets from this ruleset body and compile them separately
                    var nodeRules = rulesetNode.rules, nodeRuleCnt = nodeRules ? nodeRules.length : 0;
                    for (var i = 0; i < nodeRuleCnt; ) {
                        rule = nodeRules[i];
                        if (rule && rule.rules) {
                            // visit because we are moving them out from being a child
                            rulesets.push(this._visitor.visit(rule));
                            nodeRules.splice(i, 1);
                            nodeRuleCnt--;
                            continue;
                        }
                        i++;
                    }
                    // accept the visitor to remove rules and refactor itself
                    // then we can decide nogw whether we want it or not
                    // compile body
                    if (nodeRuleCnt > 0) {
                        rulesetNode.accept(this._visitor);
                    } else {
                        rulesetNode.rules = null;
                    }
                    visitArgs.visitDeeper = false;

                } else { // if (! rulesetNode.root) {
                    rulesetNode.accept(this._visitor);
                    visitArgs.visitDeeper = false;
                }

                if (rulesetNode.rules) {
                    this._mergeRules(rulesetNode.rules);
                    this._removeDuplicateRules(rulesetNode.rules);
                }

                // now decide whether we keep the ruleset
                if (this.utils.isVisibleRuleset(rulesetNode)) {
                    rulesetNode.ensureVisibility();
                    rulesets.splice(0, 0, rulesetNode);
                }

                if (rulesets.length === 1) {
                    return rulesets[0];
                }
                return rulesets;
            },

            _compileRulesetPaths: function(rulesetNode) {
                if (rulesetNode.paths) {
                    rulesetNode.paths = rulesetNode.paths
                        .filter(function(p) {
                            var i;
                            if (p[0].elements[0].combinator.value === ' ') {
                                p[0].elements[0].combinator = new(tree.Combinator)('');
                            }
                            for (i = 0; i < p.length; i++) {
                                if (p[i].isVisible() && p[i].getIsOutput()) {
                                    return true;
                                }
                            }
                            return false;
                        });
                }
            },

            _removeDuplicateRules: function(rules) {
                if (!rules) { return; }

                // remove duplicates
                var ruleCache = {},
                    ruleList, rule, i;

                for (i = rules.length - 1; i >= 0 ; i--) {
                    rule = rules[i];
                    if (rule instanceof tree.Declaration) {
                        if (!ruleCache[rule.name]) {
                            ruleCache[rule.name] = rule;
                        } else {
                            ruleList = ruleCache[rule.name];
                            if (ruleList instanceof tree.Declaration) {
                                ruleList = ruleCache[rule.name] = [ruleCache[rule.name].toCSS(this._context)];
                            }
                            var ruleCSS = rule.toCSS(this._context);
                            if (ruleList.indexOf(ruleCSS) !== -1) {
                                rules.splice(i, 1);
                            } else {
                                ruleList.push(ruleCSS);
                            }
                        }
                    }
                }
            },

            _mergeRules: function(rules) {
                if (!rules) {
                    return;
                }

                var groups    = {},
                    groupsArr = [];

                for (var i = 0; i < rules.length; i++) {
                    var rule = rules[i];
                    if (rule.merge) {
                        var key = rule.name;
                        groups[key] ? rules.splice(i--, 1) :
                            groupsArr.push(groups[key] = []);
                        groups[key].push(rule);
                    }
                }

                groupsArr.forEach(function(group) {
                    if (group.length > 0) {
                        var result = group[0],
                            space  = [],
                            comma  = [new tree.Expression(space)];
                        group.forEach(function(rule) {
                            if ((rule.merge === '+') && (space.length > 0)) {
                                comma.push(new tree.Expression(space = []));
                            }
                            space.push(rule.value);
                            result.important = result.important || rule.important;
                        });
                        result.value = new tree.Value(comma);
                    }
                });
            }
        };

        module.exports = ToCSSVisitor;

    },{"../tree":67,"./visitor":97}],97:[function(require,module,exports){
        var tree = require('../tree');

        var _visitArgs = { visitDeeper: true },
            _hasIndexed = false;

        function _noop(node) {
            return node;
        }

        function indexNodeTypes(parent, ticker) {
            // add .typeIndex to tree node types for lookup table
            var key, child;
            for (key in parent) {
                /* eslint guard-for-in: 0 */
                child = parent[key];
                switch (typeof child) {
                    case 'function':
                        // ignore bound functions directly on tree which do not have a prototype
                        // or aren't nodes
                        if (child.prototype && child.prototype.type) {
                            child.prototype.typeIndex = ticker++;
                        }
                        break;
                    case 'object':
                        ticker = indexNodeTypes(child, ticker);
                        break;

                }
            }
            return ticker;
        }

        var Visitor = function(implementation) {
            this._implementation = implementation;
            this._visitInCache = {};
            this._visitOutCache = {};

            if (!_hasIndexed) {
                indexNodeTypes(tree, 1);
                _hasIndexed = true;
            }
        };

        Visitor.prototype = {
            visit: function(node) {
                if (!node) {
                    return node;
                }

                var nodeTypeIndex = node.typeIndex;
                if (!nodeTypeIndex) {
                    // MixinCall args aren't a node type?
                    if (node.value && node.value.typeIndex) {
                        this.visit(node.value);
                    }
                    return node;
                }

                var impl = this._implementation,
                    func = this._visitInCache[nodeTypeIndex],
                    funcOut = this._visitOutCache[nodeTypeIndex],
                    visitArgs = _visitArgs,
                    fnName;

                visitArgs.visitDeeper = true;

                if (!func) {
                    fnName = 'visit' + node.type;
                    func = impl[fnName] || _noop;
                    funcOut = impl[fnName + 'Out'] || _noop;
                    this._visitInCache[nodeTypeIndex] = func;
                    this._visitOutCache[nodeTypeIndex] = funcOut;
                }

                if (func !== _noop) {
                    var newNode = func.call(impl, node, visitArgs);
                    if (node && impl.isReplacing) {
                        node = newNode;
                    }
                }

                if (visitArgs.visitDeeper && node && node.accept) {
                    node.accept(this);
                }

                if (funcOut != _noop) {
                    funcOut.call(impl, node);
                }

                return node;
            },
            visitArray: function(nodes, nonReplacing) {
                if (!nodes) {
                    return nodes;
                }

                var cnt = nodes.length, i;

                // Non-replacing
                if (nonReplacing || !this._implementation.isReplacing) {
                    for (i = 0; i < cnt; i++) {
                        this.visit(nodes[i]);
                    }
                    return nodes;
                }

                // Replacing
                var out = [];
                for (i = 0; i < cnt; i++) {
                    var evald = this.visit(nodes[i]);
                    if (evald === undefined) { continue; }
                    if (!evald.splice) {
                        out.push(evald);
                    } else if (evald.length) {
                        this.flatten(evald, out);
                    }
                }
                return out;
            },
            flatten: function(arr, out) {
                if (!out) {
                    out = [];
                }

                var cnt, i, item,
                    nestedCnt, j, nestedItem;

                for (i = 0, cnt = arr.length; i < cnt; i++) {
                    item = arr[i];
                    if (item === undefined) {
                        continue;
                    }
                    if (!item.splice) {
                        out.push(item);
                        continue;
                    }

                    for (j = 0, nestedCnt = item.length; j < nestedCnt; j++) {
                        nestedItem = item[j];
                        if (nestedItem === undefined) {
                            continue;
                        }
                        if (!nestedItem.splice) {
                            out.push(nestedItem);
                        } else if (nestedItem.length) {
                            this.flatten(nestedItem, out);
                        }
                    }
                }

                return out;
            }
        };
        module.exports = Visitor;

    },{"../tree":67}],98:[function(require,module,exports){
        "use strict";

// rawAsap provides everything we need except exception management.
        var rawAsap = require("./raw");
// RawTasks are recycled to reduce GC churn.
        var freeTasks = [];
// We queue errors to ensure they are thrown in right order (FIFO).
// Array-as-queue is good enough here, since we are just dealing with exceptions.
        var pendingErrors = [];
        var requestErrorThrow = rawAsap.makeRequestCallFromTimer(throwFirstError);

        function throwFirstError() {
            if (pendingErrors.length) {
                throw pendingErrors.shift();
            }
        }

        /**
         * Calls a task as soon as possible after returning, in its own event, with priority
         * over other events like animation, reflow, and repaint. An error thrown from an
         * event will not interrupt, nor even substantially slow down the processing of
         * other events, but will be rather postponed to a lower priority event.
         * @param {{call}} task A callable object, typically a function that takes no
         * arguments.
         */
        module.exports = asap;
        function asap(task) {
            var rawTask;
            if (freeTasks.length) {
                rawTask = freeTasks.pop();
            } else {
                rawTask = new RawTask();
            }
            rawTask.task = task;
            rawAsap(rawTask);
        }

// We wrap tasks with recyclable task objects.  A task object implements
// `call`, just like a function.
        function RawTask() {
            this.task = null;
        }

// The sole purpose of wrapping the task is to catch the exception and recycle
// the task object after its single use.
        RawTask.prototype.call = function () {
            try {
                this.task.call();
            } catch (error) {
                if (asap.onerror) {
                    // This hook exists purely for testing purposes.
                    // Its name will be periodically randomized to break any code that
                    // depends on its existence.
                    asap.onerror(error);
                } else {
                    // In a web browser, exceptions are not fatal. However, to avoid
                    // slowing down the queue of pending tasks, we rethrow the error in a
                    // lower priority turn.
                    pendingErrors.push(error);
                    requestErrorThrow();
                }
            } finally {
                this.task = null;
                freeTasks[freeTasks.length] = this;
            }
        };

    },{"./raw":99}],99:[function(require,module,exports){
        (function (global){
            "use strict";

// Use the fastest means possible to execute a task in its own turn, with
// priority over other events including IO, animation, reflow, and redraw
// events in browsers.
//
// An exception thrown by a task will permanently interrupt the processing of
// subsequent tasks. The higher level `asap` function ensures that if an
// exception is thrown by a task, that the task queue will continue flushing as
// soon as possible, but if you use `rawAsap` directly, you are responsible to
// either ensure that no exceptions are thrown from your task, or to manually
// call `rawAsap.requestFlush` if an exception is thrown.
            module.exports = rawAsap;
            function rawAsap(task) {
                if (!queue.length) {
                    requestFlush();
                    flushing = true;
                }
                // Equivalent to push, but avoids a function call.
                queue[queue.length] = task;
            }

            var queue = [];
// Once a flush has been requested, no further calls to `requestFlush` are
// necessary until the next `flush` completes.
            var flushing = false;
// `requestFlush` is an implementation-specific method that attempts to kick
// off a `flush` event as quickly as possible. `flush` will attempt to exhaust
// the event queue before yielding to the browser's own event loop.
            var requestFlush;
// The position of the next task to execute in the task queue. This is
// preserved between calls to `flush` so that it can be resumed if
// a task throws an exception.
            var index = 0;
// If a task schedules additional tasks recursively, the task queue can grow
// unbounded. To prevent memory exhaustion, the task queue will periodically
// truncate already-completed tasks.
            var capacity = 1024;

// The flush function processes all tasks that have been scheduled with
// `rawAsap` unless and until one of those tasks throws an exception.
// If a task throws an exception, `flush` ensures that its state will remain
// consistent and will resume where it left off when called again.
// However, `flush` does not make any arrangements to be called again if an
// exception is thrown.
            function flush() {
                while (index < queue.length) {
                    var currentIndex = index;
                    // Advance the index before calling the task. This ensures that we will
                    // begin flushing on the next task the task throws an error.
                    index = index + 1;
                    queue[currentIndex].call();
                    // Prevent leaking memory for long chains of recursive calls to `asap`.
                    // If we call `asap` within tasks scheduled by `asap`, the queue will
                    // grow, but to avoid an O(n) walk for every task we execute, we don't
                    // shift tasks off the queue after they have been executed.
                    // Instead, we periodically shift 1024 tasks off the queue.
                    if (index > capacity) {
                        // Manually shift all values starting at the index back to the
                        // beginning of the queue.
                        for (var scan = 0, newLength = queue.length - index; scan < newLength; scan++) {
                            queue[scan] = queue[scan + index];
                        }
                        queue.length -= index;
                        index = 0;
                    }
                }
                queue.length = 0;
                index = 0;
                flushing = false;
            }

// `requestFlush` is implemented using a strategy based on data collected from
// every available SauceLabs Selenium web driver worker at time of writing.
// https://docs.google.com/spreadsheets/d/1mG-5UYGup5qxGdEMWkhP6BWCz053NUb2E1QoUTU16uA/edit#gid=783724593

// Safari 6 and 6.1 for desktop, iPad, and iPhone are the only browsers that
// have WebKitMutationObserver but not un-prefixed MutationObserver.
// Must use `global` or `self` instead of `window` to work in both frames and web
// workers. `global` is a provision of Browserify, Mr, Mrs, or Mop.

            /* globals self */
            var scope = typeof global !== "undefined" ? global : self;
            var BrowserMutationObserver = scope.MutationObserver || scope.WebKitMutationObserver;

// MutationObservers are desirable because they have high priority and work
// reliably everywhere they are implemented.
// They are implemented in all modern browsers.
//
// - Android 4-4.3
// - Chrome 26-34
// - Firefox 14-29
// - Internet Explorer 11
// - iPad Safari 6-7.1
// - iPhone Safari 7-7.1
// - Safari 6-7
            if (typeof BrowserMutationObserver === "function") {
                requestFlush = makeRequestCallFromMutationObserver(flush);

// MessageChannels are desirable because they give direct access to the HTML
// task queue, are implemented in Internet Explorer 10, Safari 5.0-1, and Opera
// 11-12, and in web workers in many engines.
// Although message channels yield to any queued rendering and IO tasks, they
// would be better than imposing the 4ms delay of timers.
// However, they do not work reliably in Internet Explorer or Safari.

// Internet Explorer 10 is the only browser that has setImmediate but does
// not have MutationObservers.
// Although setImmediate yields to the browser's renderer, it would be
// preferrable to falling back to setTimeout since it does not have
// the minimum 4ms penalty.
// Unfortunately there appears to be a bug in Internet Explorer 10 Mobile (and
// Desktop to a lesser extent) that renders both setImmediate and
// MessageChannel useless for the purposes of ASAP.
// https://github.com/kriskowal/q/issues/396

// Timers are implemented universally.
// We fall back to timers in workers in most engines, and in foreground
// contexts in the following browsers.
// However, note that even this simple case requires nuances to operate in a
// broad spectrum of browsers.
//
// - Firefox 3-13
// - Internet Explorer 6-9
// - iPad Safari 4.3
// - Lynx 2.8.7
            } else {
                requestFlush = makeRequestCallFromTimer(flush);
            }

// `requestFlush` requests that the high priority event queue be flushed as
// soon as possible.
// This is useful to prevent an error thrown in a task from stalling the event
// queue if the exception handled by Node.js’s
// `process.on("uncaughtException")` or by a domain.
            rawAsap.requestFlush = requestFlush;

// To request a high priority event, we induce a mutation observer by toggling
// the text of a text node between "1" and "-1".
            function makeRequestCallFromMutationObserver(callback) {
                var toggle = 1;
                var observer = new BrowserMutationObserver(callback);
                var node = document.createTextNode("");
                observer.observe(node, {characterData: true});
                return function requestCall() {
                    toggle = -toggle;
                    node.data = toggle;
                };
            }

// The message channel technique was discovered by Malte Ubl and was the
// original foundation for this library.
// http://www.nonblocking.io/2011/06/windownexttick.html

// Safari 6.0.5 (at least) intermittently fails to create message ports on a
// page's first load. Thankfully, this version of Safari supports
// MutationObservers, so we don't need to fall back in that case.

// function makeRequestCallFromMessageChannel(callback) {
//     var channel = new MessageChannel();
//     channel.port1.onmessage = callback;
//     return function requestCall() {
//         channel.port2.postMessage(0);
//     };
// }

// For reasons explained above, we are also unable to use `setImmediate`
// under any circumstances.
// Even if we were, there is another bug in Internet Explorer 10.
// It is not sufficient to assign `setImmediate` to `requestFlush` because
// `setImmediate` must be called *by name* and therefore must be wrapped in a
// closure.
// Never forget.

// function makeRequestCallFromSetImmediate(callback) {
//     return function requestCall() {
//         setImmediate(callback);
//     };
// }

// Safari 6.0 has a problem where timers will get lost while the user is
// scrolling. This problem does not impact ASAP because Safari 6.0 supports
// mutation observers, so that implementation is used instead.
// However, if we ever elect to use timers in Safari, the prevalent work-around
// is to add a scroll event listener that calls for a flush.

// `setTimeout` does not call the passed callback if the delay is less than
// approximately 7 in web workers in Firefox 8 through 18, and sometimes not
// even then.

            function makeRequestCallFromTimer(callback) {
                return function requestCall() {
                    // We dispatch a timeout with a specified delay of 0 for engines that
                    // can reliably accommodate that request. This will usually be snapped
                    // to a 4 milisecond delay, but once we're flushing, there's no delay
                    // between events.
                    var timeoutHandle = setTimeout(handleTimer, 0);
                    // However, since this timer gets frequently dropped in Firefox
                    // workers, we enlist an interval handle that will try to fire
                    // an event 20 times per second until it succeeds.
                    var intervalHandle = setInterval(handleTimer, 50);

                    function handleTimer() {
                        // Whichever timer succeeds will cancel both timers and
                        // execute the callback.
                        clearTimeout(timeoutHandle);
                        clearInterval(intervalHandle);
                        callback();
                    }
                };
            }

// This is for `asap.js` only.
// Its name will be periodically randomized to break any code that depends on
// its existence.
            rawAsap.makeRequestCallFromTimer = makeRequestCallFromTimer;

// ASAP was originally a nextTick shim included in Q. This was factored out
// into this ASAP package. It was later adapted to RSVP which made further
// amendments. These decisions, particularly to marginalize MessageChannel and
// to capture the MutationObserver implementation in a closure, were integrated
// back into ASAP proper.
// https://github.com/tildeio/rsvp.js/blob/cddf7232546a9cf858524b75cde6f9edf72620a7/lib/rsvp/asap.js

        }).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
    },{}],100:[function(require,module,exports){
        var clone = (function() {
            'use strict';

            function _instanceof(obj, type) {
                return type != null && obj instanceof type;
            }

            var nativeMap;
            try {
                nativeMap = Map;
            } catch(_) {
                // maybe a reference error because no `Map`. Give it a dummy value that no
                // value will ever be an instanceof.
                nativeMap = function() {};
            }

            var nativeSet;
            try {
                nativeSet = Set;
            } catch(_) {
                nativeSet = function() {};
            }

            var nativePromise;
            try {
                nativePromise = Promise;
            } catch(_) {
                nativePromise = function() {};
            }

            /**
             * Clones (copies) an Object using deep copying.
             *
             * This function supports circular references by default, but if you are certain
             * there are no circular references in your object, you can save some CPU time
             * by calling clone(obj, false).
             *
             * Caution: if `circular` is false and `parent` contains circular references,
             * your program may enter an infinite loop and crash.
             *
             * @param `parent` - the object to be cloned
             * @param `circular` - set to true if the object to be cloned may contain
             *    circular references. (optional - true by default)
             * @param `depth` - set to a number if the object is only to be cloned to
             *    a particular depth. (optional - defaults to Infinity)
             * @param `prototype` - sets the prototype to be used when cloning an object.
             *    (optional - defaults to parent prototype).
             * @param `includeNonEnumerable` - set to true if the non-enumerable properties
             *    should be cloned as well. Non-enumerable properties on the prototype
             *    chain will be ignored. (optional - false by default)
             */
            function clone(parent, circular, depth, prototype, includeNonEnumerable) {
                if (typeof circular === 'object') {
                    depth = circular.depth;
                    prototype = circular.prototype;
                    includeNonEnumerable = circular.includeNonEnumerable;
                    circular = circular.circular;
                }
                // maintain two arrays for circular references, where corresponding parents
                // and children have the same index
                var allParents = [];
                var allChildren = [];

                var useBuffer = typeof Buffer != 'undefined';

                if (typeof circular == 'undefined')
                    circular = true;

                if (typeof depth == 'undefined')
                    depth = Infinity;

                // recurse this function so we don't reset allParents and allChildren
                function _clone(parent, depth) {
                    // cloning null always returns null
                    if (parent === null)
                        return null;

                    if (depth === 0)
                        return parent;

                    var child;
                    var proto;
                    if (typeof parent != 'object') {
                        return parent;
                    }

                    if (_instanceof(parent, nativeMap)) {
                        child = new nativeMap();
                    } else if (_instanceof(parent, nativeSet)) {
                        child = new nativeSet();
                    } else if (_instanceof(parent, nativePromise)) {
                        child = new nativePromise(function (resolve, reject) {
                            parent.then(function(value) {
                                resolve(_clone(value, depth - 1));
                            }, function(err) {
                                reject(_clone(err, depth - 1));
                            });
                        });
                    } else if (clone.__isArray(parent)) {
                        child = [];
                    } else if (clone.__isRegExp(parent)) {
                        child = new RegExp(parent.source, __getRegExpFlags(parent));
                        if (parent.lastIndex) child.lastIndex = parent.lastIndex;
                    } else if (clone.__isDate(parent)) {
                        child = new Date(parent.getTime());
                    } else if (useBuffer && Buffer.isBuffer(parent)) {
                        if (Buffer.allocUnsafe) {
                            // Node.js >= 4.5.0
                            child = Buffer.allocUnsafe(parent.length);
                        } else {
                            // Older Node.js versions
                            child = new Buffer(parent.length);
                        }
                        parent.copy(child);
                        return child;
                    } else if (_instanceof(parent, Error)) {
                        child = Object.create(parent);
                    } else {
                        if (typeof prototype == 'undefined') {
                            proto = Object.getPrototypeOf(parent);
                            child = Object.create(proto);
                        }
                        else {
                            child = Object.create(prototype);
                            proto = prototype;
                        }
                    }

                    if (circular) {
                        var index = allParents.indexOf(parent);

                        if (index != -1) {
                            return allChildren[index];
                        }
                        allParents.push(parent);
                        allChildren.push(child);
                    }

                    if (_instanceof(parent, nativeMap)) {
                        parent.forEach(function(value, key) {
                            var keyChild = _clone(key, depth - 1);
                            var valueChild = _clone(value, depth - 1);
                            child.set(keyChild, valueChild);
                        });
                    }
                    if (_instanceof(parent, nativeSet)) {
                        parent.forEach(function(value) {
                            var entryChild = _clone(value, depth - 1);
                            child.add(entryChild);
                        });
                    }

                    for (var i in parent) {
                        var attrs;
                        if (proto) {
                            attrs = Object.getOwnPropertyDescriptor(proto, i);
                        }

                        if (attrs && attrs.set == null) {
                            continue;
                        }
                        child[i] = _clone(parent[i], depth - 1);
                    }

                    if (Object.getOwnPropertySymbols) {
                        var symbols = Object.getOwnPropertySymbols(parent);
                        for (var i = 0; i < symbols.length; i++) {
                            // Don't need to worry about cloning a symbol because it is a primitive,
                            // like a number or string.
                            var symbol = symbols[i];
                            var descriptor = Object.getOwnPropertyDescriptor(parent, symbol);
                            if (descriptor && !descriptor.enumerable && !includeNonEnumerable) {
                                continue;
                            }
                            child[symbol] = _clone(parent[symbol], depth - 1);
                            if (!descriptor.enumerable) {
                                Object.defineProperty(child, symbol, {
                                    enumerable: false
                                });
                            }
                        }
                    }

                    if (includeNonEnumerable) {
                        var allPropertyNames = Object.getOwnPropertyNames(parent);
                        for (var i = 0; i < allPropertyNames.length; i++) {
                            var propertyName = allPropertyNames[i];
                            var descriptor = Object.getOwnPropertyDescriptor(parent, propertyName);
                            if (descriptor && descriptor.enumerable) {
                                continue;
                            }
                            child[propertyName] = _clone(parent[propertyName], depth - 1);
                            Object.defineProperty(child, propertyName, {
                                enumerable: false
                            });
                        }
                    }

                    return child;
                }

                return _clone(parent, depth);
            }

            /**
             * Simple flat clone using prototype, accepts only objects, usefull for property
             * override on FLAT configuration object (no nested props).
             *
             * USE WITH CAUTION! This may not behave as you wish if you do not know how this
             * works.
             */
            clone.clonePrototype = function clonePrototype(parent) {
                if (parent === null)
                    return null;

                var c = function () {};
                c.prototype = parent;
                return new c();
            };

// private utility functions

            function __objToStr(o) {
                return Object.prototype.toString.call(o);
            }
            clone.__objToStr = __objToStr;

            function __isDate(o) {
                return typeof o === 'object' && __objToStr(o) === '[object Date]';
            }
            clone.__isDate = __isDate;

            function __isArray(o) {
                return typeof o === 'object' && __objToStr(o) === '[object Array]';
            }
            clone.__isArray = __isArray;

            function __isRegExp(o) {
                return typeof o === 'object' && __objToStr(o) === '[object RegExp]';
            }
            clone.__isRegExp = __isRegExp;

            function __getRegExpFlags(re) {
                var flags = '';
                if (re.global) flags += 'g';
                if (re.ignoreCase) flags += 'i';
                if (re.multiline) flags += 'm';
                return flags;
            }
            clone.__getRegExpFlags = __getRegExpFlags;

            return clone;
        })();

        if (typeof module === 'object' && module.exports) {
            module.exports = clone;
        }

    },{}],101:[function(require,module,exports){
        'use strict';

        var asap = require('asap/raw');

        function noop() {}

// States:
//
// 0 - pending
// 1 - fulfilled with _value
// 2 - rejected with _value
// 3 - adopted the state of another promise, _value
//
// once the state is no longer pending (0) it is immutable

// All `_` prefixed properties will be reduced to `_{random number}`
// at build time to obfuscate them and discourage their use.
// We don't use symbols or Object.defineProperty to fully hide them
// because the performance isn't good enough.


// to avoid using try/catch inside critical functions, we
// extract them to here.
        var LAST_ERROR = null;
        var IS_ERROR = {};
        function getThen(obj) {
            try {
                return obj.then;
            } catch (ex) {
                LAST_ERROR = ex;
                return IS_ERROR;
            }
        }

        function tryCallOne(fn, a) {
            try {
                return fn(a);
            } catch (ex) {
                LAST_ERROR = ex;
                return IS_ERROR;
            }
        }
        function tryCallTwo(fn, a, b) {
            try {
                fn(a, b);
            } catch (ex) {
                LAST_ERROR = ex;
                return IS_ERROR;
            }
        }

        module.exports = Promise;

        function Promise(fn) {
            if (typeof this !== 'object') {
                throw new TypeError('Promises must be constructed via new');
            }
            if (typeof fn !== 'function') {
                throw new TypeError('Promise constructor\'s argument is not a function');
            }
            this._40 = 0;
            this._65 = 0;
            this._55 = null;
            this._72 = null;
            if (fn === noop) return;
            doResolve(fn, this);
        }
        Promise._37 = null;
        Promise._87 = null;
        Promise._61 = noop;

        Promise.prototype.then = function(onFulfilled, onRejected) {
            if (this.constructor !== Promise) {
                return safeThen(this, onFulfilled, onRejected);
            }
            var res = new Promise(noop);
            handle(this, new Handler(onFulfilled, onRejected, res));
            return res;
        };

        function safeThen(self, onFulfilled, onRejected) {
            return new self.constructor(function (resolve, reject) {
                var res = new Promise(noop);
                res.then(resolve, reject);
                handle(self, new Handler(onFulfilled, onRejected, res));
            });
        }
        function handle(self, deferred) {
            while (self._65 === 3) {
                self = self._55;
            }
            if (Promise._37) {
                Promise._37(self);
            }
            if (self._65 === 0) {
                if (self._40 === 0) {
                    self._40 = 1;
                    self._72 = deferred;
                    return;
                }
                if (self._40 === 1) {
                    self._40 = 2;
                    self._72 = [self._72, deferred];
                    return;
                }
                self._72.push(deferred);
                return;
            }
            handleResolved(self, deferred);
        }

        function handleResolved(self, deferred) {
            asap(function() {
                var cb = self._65 === 1 ? deferred.onFulfilled : deferred.onRejected;
                if (cb === null) {
                    if (self._65 === 1) {
                        resolve(deferred.promise, self._55);
                    } else {
                        reject(deferred.promise, self._55);
                    }
                    return;
                }
                var ret = tryCallOne(cb, self._55);
                if (ret === IS_ERROR) {
                    reject(deferred.promise, LAST_ERROR);
                } else {
                    resolve(deferred.promise, ret);
                }
            });
        }
        function resolve(self, newValue) {
            // Promise Resolution Procedure: https://github.com/promises-aplus/promises-spec#the-promise-resolution-procedure
            if (newValue === self) {
                return reject(
                    self,
                    new TypeError('A promise cannot be resolved with itself.')
                );
            }
            if (
                newValue &&
                (typeof newValue === 'object' || typeof newValue === 'function')
            ) {
                var then = getThen(newValue);
                if (then === IS_ERROR) {
                    return reject(self, LAST_ERROR);
                }
                if (
                    then === self.then &&
                    newValue instanceof Promise
                ) {
                    self._65 = 3;
                    self._55 = newValue;
                    finale(self);
                    return;
                } else if (typeof then === 'function') {
                    doResolve(then.bind(newValue), self);
                    return;
                }
            }
            self._65 = 1;
            self._55 = newValue;
            finale(self);
        }

        function reject(self, newValue) {
            self._65 = 2;
            self._55 = newValue;
            if (Promise._87) {
                Promise._87(self, newValue);
            }
            finale(self);
        }
        function finale(self) {
            if (self._40 === 1) {
                handle(self, self._72);
                self._72 = null;
            }
            if (self._40 === 2) {
                for (var i = 0; i < self._72.length; i++) {
                    handle(self, self._72[i]);
                }
                self._72 = null;
            }
        }

        function Handler(onFulfilled, onRejected, promise){
            this.onFulfilled = typeof onFulfilled === 'function' ? onFulfilled : null;
            this.onRejected = typeof onRejected === 'function' ? onRejected : null;
            this.promise = promise;
        }

        /**
         * Take a potentially misbehaving resolver function and make sure
         * onFulfilled and onRejected are only called once.
         *
         * Makes no guarantees about asynchrony.
         */
        function doResolve(fn, promise) {
            var done = false;
            var res = tryCallTwo(fn, function (value) {
                if (done) return;
                done = true;
                resolve(promise, value);
            }, function (reason) {
                if (done) return;
                done = true;
                reject(promise, reason);
            });
            if (!done && res === IS_ERROR) {
                done = true;
                reject(promise, LAST_ERROR);
            }
        }

    },{"asap/raw":99}],102:[function(require,module,exports){
        'use strict';

//This file contains the ES6 extensions to the core Promises/A+ API

        var Promise = require('./core.js');

        module.exports = Promise;

        /* Static Functions */

        var TRUE = valuePromise(true);
        var FALSE = valuePromise(false);
        var NULL = valuePromise(null);
        var UNDEFINED = valuePromise(undefined);
        var ZERO = valuePromise(0);
        var EMPTYSTRING = valuePromise('');

        function valuePromise(value) {
            var p = new Promise(Promise._61);
            p._65 = 1;
            p._55 = value;
            return p;
        }
        Promise.resolve = function (value) {
            if (value instanceof Promise) return value;

            if (value === null) return NULL;
            if (value === undefined) return UNDEFINED;
            if (value === true) return TRUE;
            if (value === false) return FALSE;
            if (value === 0) return ZERO;
            if (value === '') return EMPTYSTRING;

            if (typeof value === 'object' || typeof value === 'function') {
                try {
                    var then = value.then;
                    if (typeof then === 'function') {
                        return new Promise(then.bind(value));
                    }
                } catch (ex) {
                    return new Promise(function (resolve, reject) {
                        reject(ex);
                    });
                }
            }
            return valuePromise(value);
        };

        Promise.all = function (arr) {
            var args = Array.prototype.slice.call(arr);

            return new Promise(function (resolve, reject) {
                if (args.length === 0) return resolve([]);
                var remaining = args.length;
                function res(i, val) {
                    if (val && (typeof val === 'object' || typeof val === 'function')) {
                        if (val instanceof Promise && val.then === Promise.prototype.then) {
                            while (val._65 === 3) {
                                val = val._55;
                            }
                            if (val._65 === 1) return res(i, val._55);
                            if (val._65 === 2) reject(val._55);
                            val.then(function (val) {
                                res(i, val);
                            }, reject);
                            return;
                        } else {
                            var then = val.then;
                            if (typeof then === 'function') {
                                var p = new Promise(then.bind(val));
                                p.then(function (val) {
                                    res(i, val);
                                }, reject);
                                return;
                            }
                        }
                    }
                    args[i] = val;
                    if (--remaining === 0) {
                        resolve(args);
                    }
                }
                for (var i = 0; i < args.length; i++) {
                    res(i, args[i]);
                }
            });
        };

        Promise.reject = function (value) {
            return new Promise(function (resolve, reject) {
                reject(value);
            });
        };

        Promise.race = function (values) {
            return new Promise(function (resolve, reject) {
                values.forEach(function(value){
                    Promise.resolve(value).then(resolve, reject);
                });
            });
        };

        /* Prototype Methods */

        Promise.prototype['catch'] = function (onRejected) {
            return this.then(null, onRejected);
        };

    },{"./core.js":101}],103:[function(require,module,exports){
// should work in any browser without browserify

        if (typeof Promise.prototype.done !== 'function') {
            Promise.prototype.done = function (onFulfilled, onRejected) {
                var self = arguments.length ? this.then.apply(this, arguments) : this
                self.then(null, function (err) {
                    setTimeout(function () {
                        throw err
                    }, 0)
                })
            }
        }
    },{}],104:[function(require,module,exports){
// not "use strict" so we can declare global "Promise"

        var asap = require('asap');

        if (typeof Promise === 'undefined') {
            Promise = require('./lib/core.js')
            require('./lib/es6-extensions.js')
        }

        require('./polyfill-done.js');

    },{"./lib/core.js":101,"./lib/es6-extensions.js":102,"./polyfill-done.js":103,"asap":98}]},{},[2])(2)
});